18650 go with the panasonic 2900 or 3400mAh. Protected is best but some lasers don't like protected circuits so unprotected is fine as long as you don't drain it below 2.7v
Good to intro yourself on the welcome page if you haven't and do a search too. Others will appreciate IT Otherwise, you might find it a headache deciding for yourself amidst the din like : HERE
18650 go with the panasonic 2900 or 3400mAh. Protected is best but some lasers don't like protected circuits so unprotected is fine as long as you don't drain it below 2.7v