Oetiker clamps. One claimed advantage is equal pressure around the clamp. They can be cut off with a pair of side cutters, dikes (wire cutters) or bull-nose dikes (sometimes called "end nippers"). Here's a cheap crimper, just as an example. Some crimpers use the end, some use the side and I've heard about a set that does end and side. Accessabilty can dictate which crimper is used: Amazon.com: Ideal-Tridon 61001V Crimp Clamp Tool: Automotive Amazon.com: Ideal-Tridon 61001V Crimp Clamp Tool: Auto