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This is a charity listing. All proceeds go to The New Nicotine Alliance UK - Promoting and supporting tobacco harm reduction.

10 Heat Shrink 18650 Battery Wraps.

The New Nicotine Alliance (UK) is a registered Charitable Incorporated Organisation in the UK (#1160481)
NNA UK is concerned with improving public health, through a greater understanding of “new” (risk-reduced) nicotine products and their uses
For more information: https://nnalliance.org

Instructions

Pinch the cover to open it up, slide the battery into the cover, (they will be a snug fit) line up the top and bottom of the cover and heat with a hairdryer on a hot setting.
The cover will tighten itself around the battery, as the heat shrinks it.  Make sure to heat the top of the cover first, and work your way down it until you get to the bottom and then tighten that over the end of the battery.
It is recommended to remove the old cover and if you do make sure to keep the black or white insulator from the top of the old battery cover, and fit it into the same place in the new wrap.