Toddleroo Window and Door wedge locks 4 pack- 2 of them, so 8 wedges in total

They prevent children from sliding windows and doors open. Multifunctional. Works on double hung and horizontal sliding windows and doors. Limits the height the window or door can open. Easy hook and loop installation, no tools, no screws, no nails, no damage to your window, or your sliding doors. I opened one package but replaced it once I realized we couldn't use them.