8" Hand Cup for Flat Surfaces with Low Vacuum Audio Alarm

Wood's Powr-Grip N4950WBP — 8" All-Metal Handle Vacuum Hand Cup for Flat Surfaces with Low Vacuum Audio Alarm (125 lbs / 57 kg)

The Wood's Powr-Grip N4950WBP is the premium safety version of the standard N4950, adding a Low Vacuum Audio Alarm (LVAA) that emits an audible warning from the plunger when vacuum pressure drops to a critical level — providing a second, independent safety alert that does not require the operator to maintain visual contact with the red-line indicator during a lift. Featuring an 8" (20 cm) standard rubber suction pad (Model G0695), an all-metal handle and plunger, and a rated load capacity of 125 lbs (57 kg) on flat smooth, nonporous surfaces, the N4950WBP delivers the same high-capacity flat-surface performance as the N4950 with an additional layer of audible vacuum loss protection. A key operational advantage: the audio alarm automatically powers on and off as needed, extending battery life and eliminating the need for a manual on/off switch — the alarm is always ready without requiring the operator to remember to activate it. Battery powered (AAA battery included). The N4950WBP (SKU: 91507, Model: N4950WBP) is manufactured by Wood's Powr-Grip and ships with a protective carrying case.

The N4950WBP is identical to the N4950 in pad (G0695), capacity (125 lb), handle construction (all-metal), and surface ratings (flat, smooth, nonporous). The sole differentiator is the Low Vacuum Audio Alarm plunger with auto-on/off functionality. In any lift where the operator cannot continuously monitor the red-line indicator — overhead glass installation, multi-person coordinated lifts, noisy construction environments, or any application where safety regulations require redundant vacuum loss alerting — the N4950WBP is the correct and safer choice over the standard N4950.

Key Features & Benefits

Low Vacuum Audio Alarm (LVAA) with Auto On/Off — Audible Warning During Vacuum Loss

The N4950WBP’s defining feature is its Low Vacuum Audio Alarm plunger, which emits an audible warning signal when vacuum pressure drops to a critical level during a lift. Unlike a manually switched alarm, the N4950WBP’s audio alarm automatically powers on and off as needed — activating when the cup is in use and deactivating when it is not, without any action required from the operator. This auto-on/off design extends battery life significantly compared to a continuously powered alarm, and eliminates the risk of the operator forgetting to activate the alarm before a lift. The alarm is always ready when the cup is in use. The LVAA is battery-powered (AAA battery included and user-replaceable).

Dual Safety Alerting — Audio Alarm Plus Red-Line Visual Indicator

The N4950WBP retains the standard red-line visual indicator in addition to the audio alarm, providing two independent vacuum loss warning channels. The visual indicator remains the primary monitoring tool during lifts where the operator can see the cup; the audio alarm provides backup alerting when visual monitoring is not possible or is interrupted. This dual-channel safety design makes the N4950WBP the highest-safety-specification 8" flat-surface hand cup in the standard WPG lineup.

All-Metal Handle and Plunger — Maximum Durability

Both the handle and plunger are constructed from metal, providing maximum structural rigidity and long-term durability for repeated heavy-duty professional use. The all-metal construction resists deformation under sustained heavy loads and delivers consistent vacuum engagement and release action over the tool’s service life. The audio alarm mechanism is integrated into the metal plunger assembly and powered by the AAA battery.

125 lb (57 kg) Rated Load Capacity

The N4950WBP is rated for loads up to 125 lbs (57 kg) on flat, smooth, nonporous surfaces — identical to the standard N4950. The audio alarm is especially valuable at or near the rated capacity limit, where vacuum loss would result in a sudden drop of a heavy load. Always confirm the actual panel weight before selecting this tool for a lift.

8" Standard Rubber Suction Pad (Model G0695)

The 8" (20 cm) G0695 pad provides a large contact area for strong, stable vacuum retention on flat smooth surfaces. The G0695 pad is shared with the N4950 and N4000, making replacement pads interchangeable across all three models. Replacement pads are available separately through Wood’s Powr-Grip authorized distributors.

AAA Battery Included — Protective Carrying Case Included

The N4950WBP ships with an AAA battery installed and ready for use. The auto-on/off design extends battery life compared to continuously powered alarms — but verify battery condition before each use session to ensure the alarm is operational. The N4950WBP ships with a protective carrying case that keeps the pad clean and protected between uses.

Common Applications

Overhead Glass Installation

Glaziers installing overhead glass panels — including skylights, overhead curtain wall units, and ceiling glass — use the N4950WBP where the operator is looking upward during the lift and cannot maintain visual contact with the red-line indicator. The audio alarm provides the critical vacuum loss warning that the visual indicator cannot deliver in this orientation, and the auto-on/off design ensures the alarm is active without requiring the operator to remember to switch it on before the lift.

High-Noise Construction Environments

On active construction sites where ambient noise is high, the audio alarm provides a vacuum loss warning that can be heard by the operator and nearby personnel. Confirm the alarm volume is adequate for your specific noise environment before relying on it as the primary warning channel in high-noise settings.

Multi-Person Coordinated Lifts

In multi-person lifts where the operator holding the cup is not the person monitoring the load, the audio alarm alerts all personnel in the vicinity to vacuum loss — not just the person with a direct sightline to the indicator. The auto-on/off design ensures the alarm is always active during the lift without requiring coordination between operators to activate it.

Safety-Regulated Environments

In environments where safety regulations, site safety plans, or insurance requirements mandate redundant vacuum loss alerting for overhead or heavy panel lifts, the N4950WBP’s dual-channel audio+visual alarm system satisfies requirements that the standard N4950’s visual-only indicator cannot meet.

Heavy Flat Glass and Stone Panel Handling

For any heavy flat glass, stone, or panel handling application at or near the 125 lb capacity limit, the N4950WBP’s audio alarm provides an additional safety margin by alerting the operator to vacuum loss before a catastrophic drop can occur.

Compatible Materials

• Plate glass and float glass (flat)
• Tempered and laminated safety glass (flat)
• Polished granite, marble, and engineered stone (flat)
• Smooth painted or coated metal panels (flat)
• Glazed ceramic and polished porcelain tile (flat)
• Any smooth, nonporous flat surface requiring safe manual lifting up to 125 lbs — particularly overhead or high-risk lift applications

Not compatible with: curved surfaces (flat only); rough, textured, or porous surfaces; surfaces contaminated with oil, wax, or debris in the pad contact area; concrete, brick, unpolished stone, wood, or drywall.

Product Documents

• N4950WBP Instructions — Low Vacuum Audio Alarm (PDF)
• N4950WBP Troubleshooting Guide (PDF)
• N4950WBP Specifications — Low Vacuum Audio Alarm (PDF)

Application Instructions

Step 1: Pre-Use Battery Check

1. Verify the AAA battery is installed and in good condition — test the audio alarm function before each use session. The auto-on/off design means the alarm activates automatically when the cup is in use, but a dead battery will disable the alarm entirely, leaving only the red-line visual indicator.
2. Confirm the audio alarm is audible in your specific work environment — in high-noise environments, verify the alarm volume is sufficient to be heard over ambient noise before relying on it as a warning channel.

Step 2: Surface Assessment

1. Confirm the surface is smooth, flat, and nonporous — do not proceed on rough, textured, porous, or curved surfaces.
2. Clean the pad contact area — remove dust, oil, moisture, and debris.
3. Verify the panel weight does not exceed 125 lbs (57 kg).

Step 3: Pad Inspection and Preparation

1. Inspect the G0695 suction pad for cuts, cracks, hardening, or contamination. Replace if damaged.
2. Wipe the pad face clean before each lift.
3. Ensure the pad is at operating temperature (above 10°F / -12°C) before use.

Step 4: Attaching the Cup

1. Position the pad flat against the surface with full perimeter contact across the 8" diameter.
2. Engage the vacuum mechanism using the metal handle/plunger — the audio alarm will activate automatically as the cup engages.
3. Check the red-line vacuum indicator — confirm it shows a stable, full vacuum before lifting.
4. Apply a controlled test load (firm downward pull) to verify seal integrity before committing to the full lift.

Step 5: Lifting, Positioning, and Release

1. Lift smoothly — avoid sudden jerking motions that can break the vacuum seal.
2. Monitor the red-line indicator when possible; rely on the audio alarm as the backup warning channel when visual monitoring is not possible (e.g., overhead lifts).
3. If the audio alarm sounds during a lift, lower the load immediately to a stable surface — do not attempt to continue the lift or reposition the panel.
4. Do not exceed the 125 lb (57 kg) rated load capacity.
5. Lower the load fully to a stable surface before releasing the vacuum — the audio alarm will deactivate automatically when the cup disengages.
6. Engage the release mechanism slowly and in a controlled manner.
7. Clean the pad after use and store in the supplied protective carrying case.

Technical Specifications

Safety Data Summary

Hazard Information

• A dead or discharged battery disables the audio alarm — verify battery condition before every use session; the red-line visual indicator remains active regardless of battery state
• The auto-on/off design extends battery life but does not eliminate the need to verify battery condition before use — a depleted battery will disable the alarm without warning
• The audio alarm volume may not be sufficient in all high-noise environments — verify alarm audibility in your specific work environment before relying on it as the primary warning channel
• If the audio alarm sounds during a lift, lower the load immediately — do not attempt to continue the lift
• Vacuum loss during a lift can result in sudden load drop, causing serious injury or property damage
• Overloading beyond 125 lbs (57 kg) rated capacity may cause sudden cup release without warning
• Use on curved, rough, textured, or porous surfaces will prevent a full pad seal — flat surfaces only
• Damaged or contaminated suction pads must be replaced before use
• Operating below 10°F (-12°C) may degrade rubber pad performance and vacuum retention
• Do not use above 5,000 ft (1,500 m) elevation

Personal Protective Equipment

• Safety glasses or face shield when handling glass panels
• Cut-resistant gloves rated for glass and stone handling
• Steel-toed safety footwear
• Hard hat when working in overhead or multi-level environments
• Hearing protection where required — note that hearing protection may reduce the audibility of the audio alarm; assess alarm audibility with PPE in place before relying on it

Safe Handling

• Verify battery condition before every use session — the auto-on/off design does not eliminate the need for this check
• Confirm audio alarm audibility in your specific work environment, including with any PPE worn
• Inspect the pad and clean the contact area before each lift
• Never exceed the rated 125 lb load capacity
• Lower the load immediately if the audio alarm sounds or if vacuum loss is detected on the red-line indicator
• Store in the supplied carrying case to protect the pad between uses

Frequently Asked Questions

Q: What does "automatically powers on or off as needed" mean?
A: The N4950WBP’s audio alarm is designed to activate automatically when the cup is in use and deactivate when it is not — without requiring the operator to manually switch the alarm on or off. This auto-on/off design extends battery life significantly compared to a continuously powered alarm, and eliminates the risk of the operator forgetting to activate the alarm before a lift. The alarm is always ready when the cup is engaged, with no additional steps required from the operator.

Q: What is the difference between the N4950WBP and the standard N4950?
A: The N4950WBP is identical to the N4950 in pad (G0695), capacity (125 lb), handle construction (all-metal), and surface ratings (flat, smooth, nonporous). The sole difference is the Low Vacuum Audio Alarm plunger with auto-on/off functionality, which adds an audible vacuum loss warning to the standard red-line visual indicator. Choose the N4950WBP for overhead lifts, high-noise environments, multi-person lifts, or any application where visual monitoring of the red-line indicator is not continuously possible; choose the standard N4950 for standard flat-surface applications where the visual indicator is sufficient.

Q: How does the N4950WBP differ from the N5450WBP?
A: Both are all-metal flat-surface cups with the Low Vacuum Audio Alarm. The N4950WBP uses the 8" G0695 pad with 125 lb capacity; the N5450WBP uses the 9" G0725 pad with 150 lb capacity. Choose the N4950WBP for 125 lb applications where the 8" pad is appropriate; choose the N5450WBP for higher-capacity 150 lb applications requiring the larger 9" pad. Both feature the LVAA with AAA battery.

Q: What happens if the battery dies during a lift?
A: If the battery is dead or discharged, the audio alarm will not function — but the red-line visual indicator remains active regardless of battery state. Always verify battery condition before each use session. The auto-on/off design extends battery life, but does not eliminate the need for this check — a depleted battery will disable the alarm without warning.

Q: Is the G0695 pad interchangeable with the standard N4950 and N4000?
A: Yes. The N4950WBP, N4950, and N4000 all use the G0695 standard rubber pad (8" diameter), making replacement pads interchangeable across all three models. Replacement pads are available separately through Wood’s Powr-Grip authorized distributors.

Q: Is this product made to order?
A: Yes. This product is made to order and all sales are final. Please confirm your surface type, load requirements, and application environment before placing your order.

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