Units are made with Edison base fuseholder so they will take dual element plug fuse or proper size adapter for dual element fuse., U., L., listed About this item Receptacle & Fuse Holder Mounted On 2-1/8 Handy Box Cover Dimensions: 6.75L x 3.88W x 2.25H Includes fuseholder, plus a plug-in receptacle, switch, pilot light Covers fit standard outlet or switch boxes, making it easy to turn an ordinary outlet or switch box into a motor protective device Units are made with Edison base fuseholder so they will take dual element plug fuse... For supplemental circuit and small motor protection ATC High Amp Fuse Assortment Cooper Bussmann BP/ATC-A5-RP NEW Motor Protection Electrical Cover Bussman BP/SSU 2-1/4" 1/2 HP 15 Amp On/Off Fused Switch Box Cover Electrical Box Steel Cover Covers fit standard outlet or switch boxes, making it easy to turn an ordinary outlet or switch box into a motor protective device. Bussmann by Eaton - BP/SRU - FUSETRON BOX COVER UNIT - RS Includes fuseholder, plus a plug-in receptacle, switch, pilot light. Fuse holder/three prong receptacle.