The lycra extension bar is designed for use with a Gearhart style yarn topper….the kind where the two holes that feed yarn through are close together. Lycra will give your socks more memory and a slightly snugger fit. The lycra must be run through the knitting machine separately from the yarn, it does not need to go through the yarn brake or tensioning device. In fact, if it does go through with the tensioning device it will get caught up and become a tangled mess. Use this bar to separate your lycra from your yarn as it feeds into the machine. Examine the pictures carefully for installation instructions. The lycra should feed into the machine through the black grommet, keeping it away from the yarn brake assembly. Please note: there are two rubber washers. These washers will protect the powdercoat from getting damaged with use of this extension.