Threshold seals are spring loaded to lift clear of the floor as soon as the door leaf is opened by few millimeters mounted onto a 15 mm * 34 mm groove made into the bottom rail of the door these are operated automatically by pressure these can also be fited into the bottom rail of aluminium/steel doors by fabricators the seals are tested for durability for 500000 cycles without failure these are available in various seal lengths like 380 mm 600 mm 820 mm 915 mm 1070 mm and 1220 mm the seal material is made of pvc black polypile bristles these have screws for sealing action adjustment
