FeaturesClosely spaced groves for excellent twisting powerDeep, wide throat ensures full insulation coverageFunneled entry helps wires into threaded compression compartmentSpringless inner surface of cap threaded to secure conductors with the same efficiency as a springFor high temperature furnace/oven or other intense heat applications up to 645 deg CExcellent grip(2) 18 AWG to (2) 16 with (2) 18 AWG wire combinationsThree sizes accommodate 18 to 14 AWG stranded copper