Mersen class G fuse blocks accommodate 15 ampere class G fuses. A screw connectors fit a wide range of stranded or solid copper wire. Insulators are glass-filled polycarbonate (GFPC) with verified dielectric strength in excess of 2500V. Fuse blocks feature which can be snapped onto 3-pole blocks to form multi-pole segmented blocks of as many poles as desired. All fuse clips are made of high conductivity tin-plated copper alloy. Recommended fuse usage: Class G blocks use with AG. Temperature/flammability: GFPC insulators rated 125 degree C RTI, 94V-0 flammability. Approvals: all fuse blocks meet the requirements of UL 4248: UL listed guide IZLT, file E52283; CSA certified class 6225, file 32169. Torque in 20 pounds. 10kA short-circuit current rating.