cigarette lighter plug dummy cover

So I recently added a 1-to-3 Cigarette lighter plug adapter for my car, but i am only needing 2figure i will need something to cover the 3rd so that i won't accidently drop something and short out the fuse. however i can't seem to find one that has friction/spring to hold it in. naturally i decide to make one and share.the default version has a diameter of 20.8mm, standard i can found out there is 20.73-20.88mm so hopefully it should fit. if it happen that your car is having a smaller one. you might need to scale it down accordingly. my version printed with 0.2mm layer 5% infill, i personally don't think it needs to be any more than that but feel free to change it if you think it is necessary.