These ring terminals feature vinyl insulation and copper connection material. Item: Ring Terminal Insulation Type: Vinyl Stud Size: 1/4 Wire Range: 16 to 14 AWG Insulation Color: Blue Seam: Brazed Max. Temp.: 221 Degrees F Max. Voltage: 600V Overall Length: 1.150 Connection Material: Copper Standards: UL Listed E9809, CSA Certified Terminal Connection: Crimp UPC 696333644228 Color Blue Terminal Ring Terminal Stud Size 1/4 inch Brand Name CAI - STA-KON Manufacturer CAI - STA-KON Material Type Vinyl Connector Type Ring Maximum Voltage 600 Volts Contact Material Copper Specification Met CSA, UL Temperature Rating 221 degree fahrenheit Insulation Material Type Polyvinyl Chloride