Clear Switch Lock for Light Switch 4/pack by National Mfg.
Amazon.com: 2 Light Switch Guards Optional Wall Plate Cover Switch Cover Light Switch Lockout Light Switch on Off Guard in White for Lights Circuits Protection from Accidentally Turned on or Off, Not
BRADY, For Toggle Switch Type, For 1.161 in Max Switch Wd, Wall Switch Lockout - 2AF98|65696 - Grainger