☞CONVENIENT LOCKING — The button style switch is 4-way, twist in and out, totally locked. ☞ IMPROVED WEATHER RESISTANT BRUSH TRAIN — Provides a fixed groove with locking tabs for the weather resistant brush strip , firmly fixes the brush strip. Even if the brush comes off, it is easy to put it back in the fixed slot. This greatly helps the brush bar to reduce noise, stop rain, wind or pests like mosquitoes as much as possible. ☞ DANGER FOR SCREWS — Comes with 2 packs of 8 screws each, one with short screws and the other with screws long. Please screw on both sides to avoid cracking, not just one side. You can make 8 screws for the 4 screw holes with the long+long, long+short or short+short group depending on the depth of the door/wall to be installed. ☞APPLICABLE TO — Inner size 1515.5. And the exterior size is 195.5*22 It can be installed on interior door, exterior door, wall, window, cabinet, glass, etc.