Kẹp Dây Giày

My son got a new pair of shoes/slippers that weren't designed to be tied, with knots at the end of the laces to prevent them from pulling back through the eyelets. However, the eyelets were sewn rings, rather than a plastic or metal ring, and so his laces kept pulling back through the eyelets. 

Scale to your needs, as uploaded, the inner diameter is 1.5mm. For stretchy laces, I suggest keeping the inner diameter a few mm smaller than the lace, for non-stretchy laces it may need to be close or slightly less than the lace diameter. 

Stretch the laces and snap on the keeper. No more loos laces!