Spring Cord End Stop Lock Toggle 3mm 4mm Cord Elastic 2 HOLE BUY 2 4 Or 8 866D
£5.70
These have 2 holes. Each hole is can take a 3mm cord but I have also managed to get up to a 4mm cord though as well. It depends on if it can squash down. 3mm 4mm Cord Lock Adjuster. The more you buy the better the price per clasp.
