Door security chain with alarm

摘要

Door security chain 11 primarily for UPVC doors. A support 4 secured to a wall supports the chain 11 and an alarm 6. The chain has a ring 12 to engage over a door handle and a link 10 attaches to a fixed eye bolt 9 to limit door opening. If the door is forced open then link 10 breaks and allows the chain to pull an alarm activation pin 14. The arrangement does not require holes to be drilled in the door or frame.