There are two type of radiator hose fastener commonly used, 1. screw type 2. spring clamps. Most of the vehicle owner prefer to use the screw type clamp, this clamp seem doing the job best. Fortunately for the upper or lower radiator hose which hold pressure this screw type is not the best.
Over the time the rubber (radiator hose) will flatten/shrink but the clamp maintain its condition/position. This will lead to water/coolant spray out within the hose end.
So the best clamp to use is spring type, even the hose flatten/shrink the clamp will continue doing his job, because the spring type keep clamping as hose shrink.
The screw types is also dangerous if you not properly tighten the screw. As you tighten the screw the lower part of the clamps that move will scratch the hose and making hole without anyone notice it. The harder you tighten up the screw the deeper the metal push inside the hose and created bigger holes.
spring type clamps. picture wikipedia
screw type clamps. pictures wikipedia
