The RovyVon E300s is quite big for a keychain light!
See the comparison between the E300s and its siblings Aurora A2 and A5R, “true” keychain lights:
For more information, see the thread:
A nice alternative can be the new RovyVon A23 (XP-L [6500K-7000K] / Nichia Version [4500K-5000K], 1000 lumens [probably less on the Nichia), 600mAh, USB rechargeable): https://www.rovyvon.com/products/a23?variant=29510580273255