A cushioned P clamp with a 6.4mm inside diameter, the smallest in the range. At this size it is generally holding vacuum lines, small fluid tubing, sender wiring and individual cable runs rather than main plumbing. Small lines are the ones most often left loose and are exactly the ones that fail first, chafing through against a bracket or a moving component before anyone notices. The cushion inside the band grips without crushing thin-walled tube and stops the metal edge cutting in. Use them liberally, since they cost little; just check the outside diameter of what you are securing so the clamp neither pinches nor allows movement.