Product Name: Zpacks Trekking Pole Jack ★ Brand new, unused ★ Imported and sold under a Zpacks authorized reseller license. ★ Immediate purchase OK. Attaches to the tip of a trekking pole to extend its length, useful for setting up tall tarps and tents. It has an insert to catch the tip of the trekking pole and keep it centered and vertical. The insert is attached to a spring and can be adjusted for various tip lengths. Fits almost all pointed trekking pole tips. Using this pole jack increases the pole height by approximately 10 to 10.5 inches (26 cm).