[Size] About 8mm in outer diameter, 18mm in total length, 3.4mm in hole diameter.[Material] - These shoelace locks are made of aluminum alloy, which is lightweight, sturdy and has long-lasting durability. It is compact and comfortable with a cylindrical shape.[Tieless and Anti-loose Design] No tie shoe lace locks designed for anti-loose shoelace motion. Once you lock, no need to worry the shoelace will loose even though you walk or do an exercise for a long time.[Application] Shoelace buckles commonly used on boots, sports shoes, canvas shoes, work shoes or any other shoes need to tighten the shoelace. Meets various needs for different shoes and you can share them with your family and friends.[How to Use] Adjust the shoelace at a comfortable length(You can wear your shoes on to confirm the length); Install the screw lock and tie a knot on each side(If your shoelace is too thin, you can tie several knots.); Cut the extra shoelace and tighten the screw buckle.package6pcs Shoelace buckles(royal blue).