Bussmann CVRI-J-60200-M Fuse Block Cover. Bussmann Fuse Block Cover, Series: JM60, 200 A, 600 VAC, For Use With: Class J Power Distribution Fuse Block, 7-1/8 in Length, 2 in Width, 2-1/2 in Height, Thermoplastic. Additional Description: BUSS-CVRI-J-60200-M CLASS J 600V 200A FUSE COVER ASSEMBLY. Catalog Description: Eaton Bussmann series CVR fuse block cover, Modular fuse block cover, 200 A, Class J, With Indicator, 600 V.