Clear Switch Lock for Light Switch 4/pack by National Mfg. - Amazon.com
Toggle Shield | Light Switch Guard (3,Clear) | "Only" Compatible with Leviton Light Switch | No Tools Required | Child Proof Light Switch | Lock Switch in On Or Off Position |:
Amazon.com: Light Switch Locks Set of 6 : Handmade Products
Toggle e-Lock Light Switch Guard White
Amazon.com: Wall Switch Guard, ILIVABLE Childproof Light Switch Plate Covers Protects Your Lights or Circuits from being Accidentally Turned On or Off by Children and Adults (White, 4 Pack) : Baby