The 5820L is nearly half the size of standard door/window transmitters. It is ideal for casement and doublehung windows. The 5800 Series of door and window transmitters provide the most reliable, convenient and cost effective solutions for security protection. These devices are powerful and versatile enough to help solve even the toughest, most labor intensive installations. With a demonstrated outdoor range of over a mile, the 5800 Series has the best performance of any transmitters available today.