This is a set of two auxiliary locks (black) to prevent entry through windows. They are easy to install without tools and are useful for home security. They can be used on both the upper and lower frames and are compatible with window sashes and frames approximately 28-42mm thick. Installing them on both the top and bottom of the window will increase the security effect. Although it is an unopened, unused item, please understand that it has been stored at home. Due to the thickness, it will be shipped in simple packaging without bubble wrap via Yu-Packet Post Mini (⁎ᴗ͈ˬᴗ͈⁎) Product Name: NEW Window Lock - Size Adjustment: Approximately 28-42mm - Purpose: Security window lock - Quantity: Set of 2 - For upper and lower frames - No tools required