This is a modular killkey system I designed for my lightsaber, the killkey (or killplug) fits a standard 2.1mm connector as found on most lightsabers.

killkey_basic is a universal killkey that can be printed and you can attach a rope or ring to it. This is a ready-to-go version.

The modular system consists of two parts: First, the killkey_base, this is the part that goes into the 2.1mm connector and actually triggers the internal switch. And Second the killkey_clip, this is the cosmetic part, you can embedd it in any design you want, and it will slide right onto the killkey_base, so you can design it fully customizeable.

killkey_simple is a sample I included that shows how it works.

Have fun!