Constant Tension Clamp 5/8" 300 SS Band 3/8" 410 SS Screw SS Belleville Washers SAE J1508 Type SLHD SAE Size 812 7-1/4" to 8-1/8" size range Constant tension clamps automatically expand and contract as the temperature increases and decreases, avoiding cold water leaks. Includes an inner liner to protect soft hoses like silicone from damage due to the band serrations. Our clamps come from a 50+ year old OEM supplier to the heavy duty commercial truck market. Unlike most online sellers who just buy from the lowest bidder, we make an extra effort to find suppliers who provide high quality products that are a great value.