Step-less clamps are designed to tighten in an exact circle around the hosing, simply use a crimping tool or the middle cutter on your pliers to crimp (not squeeze) the step-less clamp closed.
For use with 3/16" ID x 5/16 OD PVC hose. The same narrow hose we use with our Picnic Tap Kit. It is a very tight fight, but it is very tidy and won't snag your clothes like a worm clamp.