DescriptionAre you looking for a professional, yet affordable spring insert assembly set? Are you in search of a sturdy, trustworthy tool that can do multiple jobs at once? If yes, look no further! Our professional spring insert assembly set must meet you needs. It is one of the best choices for you.Features- Color: As shown. - Size: 20.00X10.00X3.00cm/7.86X3.93X1.18 inch. - Material: Copper. - Suitable for distribution device, the electric power electric wire connection of electrical equipment and browsing.- Electrical crimp connectors for household, vehicle and more. Here you will find the right connectors for all your electrical wiring projects. - Comes with all you need to make solder less electrical repairs around the home, shop or outside. - Selected materials, high product safety performance, strong use and not easy to fall off. - Adopted from material, it is durable and long lasting use.Specification- 6.3 Type: Inner diameter: 6.3mm, thickness: 0.4mm(male), 0.8mm(female), compatible wire:0.75-2.5mm(AWG 18-14) - 4.8 Type: Inner diameter: 4.8mm, thickness:0.35mm(male), 0.5mm(female), compatible wire:0.75-2.5mm(AWG 18-14) - 2.8 Type: Inner diameter: 2.8mm, thickness:0.25mm(male), 0.5mm(female), compatible wire:0.5-1.5mm(AWG 22-16)