Twist-On Wire Connectors, Color Gray, For Conductor Material Copper, Maximum Temperature 221 Degrees F, Maximum Voltage 600 V, Minimum Wire Combination (1) 20 AWG with (1) 18 AWG, Maximum Wire Combination (1) 10 AWG with (2) 12 AWG, Contact Finish Zinc, Contact Material Steel, UL 94 Flammability Rating V-2, Maximum Conductors 5, Standards CE, CSA Certified, UL 486G, UL Listed, Wire Connector Style Standard, Compatible with Product Type Underground, Fill Material Silicone. This item has been restricted from sale in the following state (s): []