A turn thumb lock, also known as a thumb latch or turn lock, is a type of mechanical locking mechanism commonly used in residential and commercial buildings. It features a rotating thumb lever or knob that, when turned, releases a spring-loaded latch, allowing the door or window to be opened. The latch automatically re-engages when the lever is released, securing the opening. Turn thumb locks are often constructed with durable materials such as stainless steel or aluminum, ensuring strength and corrosion resistance. They come in various designs and finishes, making them suitable for a range of architectural styles and applications.