Size: 6. Clamp Diameter: 5/16″ – 7/8″. Fits Hose OD: 1/4″ to 7/16″. All 300 grade stainless steel marine grade clamp. These clamps are tiny, tough and precision- engineered to use in such small hose applications including emission control, fuel lines and vacuum hoses. Slim, 5/16″ bands and low profile housings allow installationin confined areas.