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Battery Adapter Tube for 18650 to 21700 Conversion Use your 18650 batteries in lights designed for 21700 cells with this precision-fit adapter tube. The adapter increases the diameter of your 18650 battery for a snug, secure fit inside compatible lights. Compatible Models: KillLight® HD4 KillLight® HD4X Gen 2 Headlamp 3-Color Pro Headlamp Features: Allows 18650 batteries to be used in 21700 battery lights Durable, lightweight design Ensures tight, rattle-free fit Simple slide-in installation Perfect for those who want to swap between battery types without hassle.
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🇺🇸 Ship from USA · On Agora since 2026
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