Oh no, not another electric car type 2 charging plug cap! Well this one incorporates a tether string and cable clip. so is a good all in one solution. It must be made in TPU or similar flexible and durable material. PLA will just break. The wide flange on the cap makes it easy to remove from the plug and also prevents the protected plug body rubbing against the wall.

I have included 2 files (3 now see below edit). One with water drain vent holes and one without. If the plug is located outside and is to hang downwards, please use the vented one. Otherwise it will fill and pool when it rains and will cause electrolytic corrosion to the pins (especially the CP pin which always has 12V present!).

UPDATE EDIT. I have recently improved the cap with the drain holes (V2). It fits plug better for easier fitting and removal, has a shorter tether and larger drain/vent holes. Also has larger size cable clip on the end of tether and hangs in a more convenient natural orientation for fitting cap to plug end (flat to top). Strongly recommend using this V2 version. Grey cap in picture is the V2. Black is the original.

If it is to hang always facing upwards outside, then use the unvented one. Also if it's inside garage or similar so never gets rained on, perhaps use the unvented one?

CAUTION: Never ever use the unvented cap outside when plug is hanging with end facing down! It WILL fill with water and cause electrolytic connector pin corrosion in no time!! You have been warned.

The clip on end will attach nicely to the thick charging cable near the plug handle. Sorry about the wonky appearance of the flexible cord! It was done in a hurry and drawn freehand with the mouse. It looks a bit weird but soon stretches out perfectly ok in use. It had to be folded else it would not have fitted within my small 200mm diameter printer bed.

If you want it straight you can easily heat it with a hair dryer whilst pulling it out straight carefully, then allow it to cool before releasing the stretch. TPU is great for this as it is very strong and durable yet stretchy at the same time. Enjoy!