"Using to feed electric under-floor heating with direct 16amp feed from fuse-board. Didn't want a neon (as on all the time) and didn't want a 13amp fuse (not reliable for continuous operation). This does the job and MK for under £4 can't be bad. Only criticism of MK are the terminal screws which often can't be tightened fully as the brass seems too soft and can snap half the screw head. You have to partially tighten, wait a few minutes and then give a final turn when the copper wires have settled into their new position."