WLB40 USB-C Rechargeable Li-ion Battery (4,000mAh)

A charged spare for your NWH20, ready to swap The WLB40 is the battery that powers the NWH20 work headlamp. Keep a second one charged and you swap in fresh power in seconds instead of waiting on a cable, so a long shift never stops for a flat battery. 4,000mAh at 3.6V, 14.4Wh of capacity USB-C charging port built into the battery, no cradle or external charger needed Recharges in about four hours from a standard 5V/1A adapter Three blue indicators show the remaining charge at the press of a button 64 grams, 80.5mm long by 24mm across Designed for Nitecore work lights, including the NWH20 4,000mAh of steady, lasting power Fourteen and a half watt-hours of capacity keeps a work headlamp running through the long, low and mid settings where most of a shift is spent. In the NWH20 that is up to 12 hours at 300 lumens or 51 hours at the 40 lumen setting on a single pack. A stable output holds performance level rather than fading as the charge drops. Recharge over USB-C, no cradle to carry The USB-C port sits on the battery itself, so it charges from the same cable and adapter you already use for a phone. A full charge takes about four hours from a 5V/1A adapter. The indicator by the port flashes blue while charging and turns steady blue once the pack is full, so you can see at a glance when it is ready. Know the charge before you head out A short press of the indicator button lights the three blue LEDs to show how much is left, then they switch off after ten seconds. Three steady lights mean 67 to 100 percent, two mean 34 to 66, and one means 11 to 33. A single flashing light means the pack is at 10 percent or below and due for a charge. It takes the guesswork out of which spare to grab. Safe and reliable The WLB40 carries multiple global certifications, so it meets recognised safety standards for a Li-ion pack that rides on your head all day. It is built as a genuine Nitecore power solution rather than an unbranded cell, which is what you want in a battery that charges over USB-C and works in wet, dusty conditions. Made for Nitecore work lights This is the dedicated pack for Nitecore work lighting, and the same battery that ships inside the NWH20 headlamp. If you run the NWH20, a spare WLB40 means one charges while the other works. The pack is 80.5mm long and 24mm across with a fixed orientation, so before using it in another light, check that model's manual or battery compartment to confirm it takes the WLB40. TECHNICAL SPECIFICATIONS Model NITECORE WLB40 Type Rechargeable Li-ion battery Capacity 4,000mAh Rated Energy 14.4Wh Nominal Voltage 3.6V Charging Port USB-C (on the battery) Charging Time Approx. 4 hours (5V/1A adapter) Charge Indicator 3 blue LEDs (press to check); flashing while charging, steady when full Length 80.5mm ±0.3mm (3.17") Diameter 24mm ±0.3mm (0.94") Weight 64g / 2.26 oz Safety Multiple global certifications (CE and more) Compatibility Nitecore work lights, including the NWH20 FREQUENTLY ASKED QUESTIONS Can I charge the WLB40 on its own, outside the headlamp? Yes. The USB-C port is on the battery itself, so it charges as a standalone pack from any USB-C cable and a 5V/1A adapter, taking about four hours. That is what lets you charge one while a second runs in the light. Will it fit my other Nitecore lights? The WLB40 is the dedicated pack for Nitecore work lights and is the battery supplied with the NWH20. It measures 80.5mm by 24mm and installs in one orientation, so check your model's manual or battery compartment to confirm it takes the WLB40 before ordering. How do I tell when it is fully charged? The indicator by the USB-C port flashes blue while charging and turns to a steady blue once the pack is full. A separate short press of the indicator button shows the remaining charge on three blue LEDs at any time. What's In The Box 1x NITECORE WLB40 Battery (4,000mAh) Keep one charged, and the light never stops. Add to cart