No assembly is required. The Bird Crash Preventer is preassembled and ready to hang on included brackets. It mounts on an outside wall.

The monofilament lines are factory-fastened to the the upper and lower curtain rods. The product arrives with the lines wound around one of the rods.   

You screw two brackets to the wall above and two below the window and place the rod with the lines wound around it on the two upper brackets horizontally. Then you unroll enough line off of it to cover the window and lock the other rod in the lower two brackets. Screws and instructions are included. It's pretty easy. (See pictures below.) 

Maximum length is 84" (214 cm) -- which  covers most windows as well as standard sliding glass door side panels. 

Two widths are available: BB3 (36" - 92cm) and BB4 (48" - 122cm). For extra wide windows mount units side by side.  It's not necessary to cover every square inch of window to prevent bird strikes. For example, you can center a BB4 model (4-feet wide) on a 5-foot wide window, thus leaving 6" (15 cm) gaps on each side.

8' window covered with two 4-foot models mounted side-by-side

Two sets of brackets are included (You select one type): 5" stand-off brackets and "L" brackets. It's most effective to leave a space between the lines and the glass. Most windows will use the 5" brackets. If your glass is already recessed, as are most sliding door panels, you don't need the 5" brackets and would use the "L" brackets instead. (See below.)

For use on sliding-door (patio-door) panels this product also includes eye -screws and plastic ties to  attach the lower rod to a wood deck.

Top of Sliding-Door Panel

Bottom Tube on a Sliding-Door Panel -- Attached to Wood Decking


Bird Crash Preventers are available in two colors: Dark Brown (similar to most "bronze" aluminum window sash) and White.