Gates 32919 PowerGrip Hose Clamp Durable nylon fiber provides extra wear resistance, doubling tooth strength Size SB19, .3/8 inch Normal hose I.D., 11/16 inch hose O.D. minimum, 13/16 inch hose O.D. maximum Maintenance-free clamps that retain dynamic tension and never need retightening Made from heat-sensitive thermoplastic with a memory to prevent over or under-tightening These clamps stop leaks, even on out-of-round application