Manual Worm Gear w Chain Travel 2m of usable chain. The chain is 4m total with 2m of hang. Our low friction Worm Gear never must be lubricated and with a higher impact plastic wheel and galvanized chain/housing will not rust or corrode.The innovative swiveling chain guide permits tension free chain pulls from directly below the gear or at an angle. The drive ends are 0.75 inch and also have holes drilled through them to secure the drive or roll-up tubes attached to ends.