Chunky lanyard cord end

This surrounds and protects knots that you've made in pull-strings, lanyards, and so on. Also called lanyard nuts, cord stops, cord ends, or cord locks.

The part is 16 mm in diameter and 12 mm tall. The exit hole is about 5 mm, which is appropriate for a lanyard made from a doubled-up shoelace. You can, of course, drill or ream this hole to suit.

I've put some half-height posts around the inside edge of the cord end; these help retain the knot inside. It also means that you can fill the cord end with hot glue, which will form around those posts and lock everything in mechanically.