Bussmann SA-15 15 Amp Single Motor Circuit Edison Base Fustat Fuse Adaptor, 4-Pack These fustat fuse adaptors screw into Edison thread fuse sockets of standard fuse boxes making it easy to retrofit existing fuse installations This product adds a great value This product is manufactured in United states Rejection Base Fuse Adapter Rejection base fuses (Type S and SL) require adapters to be used in standard Edison base sockets Once installed, rejection base adapters accept only rejection base fuses which prevents the wrong fuse size from being used Available in Amp ratings from 1A to 30A UL Listed