This is a Decora light switch stop to prevent someone from accidentally switching on or off a Decora light switch. 

If you are looking for a regular light switch stop, check this printout:
[https://makerworld.com/en/models/1108565#profileId-1104720](https://makerworld.com/en/models/1108565#profileId-1104720)

If you want to replace the entire plate that covers your switch or if you have short screws that barely catch, I have a full plate version here:

[https://makerworld.com/en/models/1192208-decora-light-switch-stop-with-plate#profileId-1204169](https://makerworld.com/en/models/1192208-decora-light-switch-stop-with-plate#profileId-1204169)