I found this one un-broken in the TPUD dumpster. The tag on it says 'A.B. Chance Matthews Cut-out'. 15kV. I assume that Matthews may have been the designer. The ribbed porcelain crossarm mounted 'salt air spacer insulator' came with it. This was used to increase the insulation amount at the coast due to salt air and fog causing flashover. There are several names for this style cutout such as 'grasshopper', 'Trip-O-Link' (possibly a brand name) and 'spring loaded'. The copper spring coil holds tension on the fuse link, which will break under excessive load, opening the circuit with a flash no doubt! The link can be replaced hot with a hotstick by slipping the rings into the holders. These rings have been pulled enough to show some use. I am looking for more of these! I maybe should have put this in 'Hunts and Finds' but it does contain a porcelain insulator!