Livart Vulcanus Butane Gas CRV- Explosion-Proof, Countersink Release Vent, UL Listed. Up to 2 hours of use per canister. Fits all Stoves designed for Butane Gas. 12 Pack - Contains 12 x 8 oz. (227 g) Individual Butane Gas Canisters. Store in a dry area away from heat. Shipped via UPS Ground only. Made in Korea. Model: GAS-1 Up to two hours of use per canister CRV Butane gas system : Countersink Vent & Triple seaming. UL approved, CRV canister will not explode, even if external heat causes excessive pressure increase in the can. Net weight per canister 8oz (227g)