SPERAS M4 v3 21700 Battery Tube | Extended Runtime

Why Upgrade to the TB217 21700 Tube?

• Unleash Peak Performance: With the higher discharge rate of a 21700 battery, the M4 V3's maximum output jumps to a blinding 2800 lumens and extends the beam distance to 740 meters.
• Extreme 500-Hour Runtime: Accommodating a 5000mAh 21700 battery drastically increases your efficiency, pushing the maximum ECO mode runtime to an incredible 500 hours for off-grid survival.
• Improved Ergonomics: The extended body length provides a comfortable, full-hand tactical grip, ideal for night patrols, search and rescue, or use with heavy gloves.
• Seamless Integration: Simply unscrew the original short body and thread on the TB217 extension. Machined from the same aerospace-grade 6061 aluminum alloy with Military Type III hard-anodizing for a perfect match.

What is the TB217 Extension Tube used for?

The TB217 is a custom-machined accessory designed specifically for the SPERAS M4 V3 flashlight. It replaces the original short battery tube, allowing the flashlight to be powered by a much larger 21700 lithium-ion battery (like a 5000mAh cell) instead of the standard 18350 battery.

Will this tube make my M4 V3 flashlight brighter?

Yes! Upgrading to a 21700 battery via the TB217 tube unlocks the flashlight's peak potential. The maximum lumen output increases from 2200lm to 2800 lumens, and the maximum beam throw distance is extended from 700m to 740 meters.

How much does the runtime improve with the 21700 battery?

The runtime sees a massive improvement. When equipped with the TB217 tube and a high-capacity 5000mAh 21700 battery, the M4 V3 can run for up to 500 hours continuously on its lowest ECO setting, making it perfect for extended camping trips or emergency blackouts.