WBT cable end sleeves are made of special oxygen-free copper and then 24k gold plated for protection. Kit dispenser contains:

WBT-0430 (250 pieces uninsulated) 20 AWG
WBT-0431 (250 pieces uninsulated) 19 AWG
WBT-0432 (150 pieces uninsulated) 17 AWG
WBT-0433 (100 pieces uninsulated) 16 AWG
WBT-0434 (100 pieces uninsulated) 14 AWG
WBT-0441 (50 pieces insulated) 16 AWG
WBT-0442 (40 pieces insulated) 14 AWG