18650 Battery Spacer Holder is a cylindrical battery spacer, made of flame retardant ABS PC materials, with high-temperature resistance and crack resistance. There are slots on the edge of the 18650 Battery Spacer Holder, that can be combined into many different sizes and shapes of the battery pack; after welding nickel tabs, the pack can pass the vibration test without any other connecting device. Make your battery pack Solid and Reliable! Note!! Every Single battery cell needs 2 Spacers one up and one down buy it accordingly. Specifications: Compatible Battery Size: 18650 Material: ABS Bore Diameter: 18.5mm 18650 Battery Spacer Holder is very simple to operate Very flexible, it is easy to assemble any type of battery packs Radiating during high-rate discharge It makes your battery pack Solid and Reliable Package Included: 1×2 Battery Cell Spacer