Review on Enhanced Vinyl Sliding Window Locks by Defender Security - Effortless Installation for Securing Windows - Durable White Diecast Construction (Pack of 2) by Robert Helstrom

This product is EXACTLY what I need to keep the window from opening more than a few inches so none of my young children can climb multiple floors climb/possibly fall onto the ground outside. It offers excellent value for money, a simple metal vise design (the underlying mechanics are grossly underrated in most devices on the market today) and is easy to install. It's worth noting that it slipped a little when I first installed the window if I opened the window hard enough, but I was afraid I'd break the window rail if I tightened the vise any further. So I cut a square from the shelf handle sheet (as shown in the photo), folded the square in half and over the window rail, placed a vise on the handle pad and tightened. Works great with no glitches! Of course, children cannot remove it, but we adults can in an emergency. Very happy with this product.