Exclusive three-layer construction prevents collapse under vacuum and ballooning/bursting under pressure. Low permeation material prevents evaporation. 60% more output per pump than leading competitors for faster engine priming. Operating temperature 18 degree F - 122 degree F. Tested to ABYC H-25 and USCG requirements. Exclusive high efficiency check valves for faster priming and low fuel restriction (less than 1kpa restriction at 50 liters/hour). Engineered hose barbs and stainless steel stepless clamps for leak free performance. Compatible with Ethanol blended fuels. EPA and CARB certified.