Ashford's warp thread weights are handy for tensioning individual threads at the back of your loom. They have a hook at top and bottom and space in between for wrapping the warp thread--perfect for replacing a broken thread or for separate weighting of floating selvedges. Add or subtract the washer weights to get the tension right. Or, if you just need to add some weight to a loose thread, you can hang a weight from it using one of the hooks. Sold as a pair.