opener consisting of a string that can be passed through a hole in a door for raising the latch from outside
latchstring详细解释
latch.string
n.（名词） A cord attached to a latch and often passed through a hole in the door to allow lifting of the latch from the outside. 栓锁带：活栓锁上的带子，通常由一个小洞通到门里以便从外边拉开活栓锁
