Stepless Spring Clamp For Thermal Cycle Applications, 1.6875 - 1.9375 Inch Clamping Range, 0.35 Inch Width

For thermal cycling, the spring automatically reacts to hose expansion, contraction, and vibration so it keeps adjusting as temps change. That continual take-up is meant to help prevent cold water leaks that show up after a heat cycle.

Silicone hoses are actually one of the better fits for this clamp. The installation torque requirement is low by design, which keeps stress off softer hose materials during tightening. The spring inside does the real work after that, automatically adjusting as the hose expands and contracts with heat cycles. You tighten the screw until the spring is fully compressed, then add three more full turns. At that point there should be a small gap of at least 1/8 inch between the two D-Nuts, and that gap tells you the clamp is properly loaded without being cranked down hard enough to bite into the hose.