ADJUSTABLE WINDOW GAP SIZE: The SAFELON Window Restrictor offers two window opening settings: 3.62 inches (9.2 cm) and 5.31 inches (13.5 cm). This adjustable gap meets daily ventilation needs while providing added safety for homes with children and pets. Material: Constructed from durable polyamide material, this window lock is designed to be strong and reliable. It helps prevent accidental window openings by children, reduces the risk of finger pinching, and helps prevent falls from windows. Suitable for use in homes with both young children and pets. Easy Lock and Unlock: Features a dual-button release mechanism that allows adults to easily lock and unlock the window for normal operation. The design has no keys or removable parts to lose. Adjust the window opening by pressing and holding the slider button on the rod, then pushing or pulling the window into position. The mechanism is simple for adults to operate but difficult for young children to manipulate. EASY INSTALLATION: The SAFELON window restrictor comes with both adhesive tape and screws to accommodate different installation preferences and surfaces. Follow included instructions for proper setup and optimal performance.