Glossary · Power
21700
The 21700 is a fatter, taller lithium cell than the 18650, holding roughly 4000–5000 mAh. It buys meaningfully more runtime and sustained output at the cost of a slightly larger light body. Many current EDC lights have moved to it.
Related terms
Reader favorites
The short list — full rankings live on the best-gear page.
Nitecore UI1 charger + 18650
$11.99
Check priceCIVIVI Elementum knife
$65.00
Check priceSureFire Stiletto Pro
$358.95
Check price
Straight disclosure —some links on this page are affiliate links. As an Amazon Associate we may earn a commission when you buy through them, at no extra cost to you. It never changes the price you pay, and it never changes a verdict.
60 guides published
42 products vetted
250 reader price checks
Featured merch
Original graphics, made to order. Gear-room aesthetics, no logos shouting.
