Check the listing for details. MSR IsoPro Fuel Canister for Backpacking and Camping Stoves, 16oz / 450g. Condition: New. Listed at 29.99 USD. MSR IsoPro is a performance-boosting, 80/20 blend of isobutane and propane, with the purest isobutane (5% or less n-butane) of any canister fuel. This clean-burning formulation maintains higher internal pressure at lower temperatures than standard butane/propane mixtures, delivering superior cold weather performance and more consistent output over the life of the canister. The 4 oz measures 3.5x3.5x2.7 inches and weighs 7.4 oz, 8 oz measures 4.3x4.3x3.7 inches and weighs 13.1 oz and 16 oz measures 4.4x4.4x6 inches and weighs 1lb 7 oz.MSR IsoPro is a performance-boosting, 80/20 blend of isobutane and propane, with the purest isobutane (5% or less n-butane) of any canister fuel. This clean-burning formulation maintains higher internal pressure at lower temperatures than standard butane/propane mixtures, delivering superior cold weather performance and more consistent output over the life of the canister. The 4 oz measures 3.5x3.5x2.7 inches and weighs 7.4 oz, 8 oz measures 4.3x4.3x3.7 inches and weighs 13.1 oz and 16 oz measures 4.4x4.4x6 inches and weighs 1lb 7 oz.