Closers or openers for wings, not otherwise provided for in this subclass spring-actuated {, e.g. for horizontally sliding wings } for swinging wings {, e.g. counterbalance } with double-acting springs, e.g. for closing and opening or checking and closing {no material}
Closers or openers for wings, not otherwise provided for in this subclass spring-actuated {, e.g. for horizontally sliding wings } for swinging wings {, e.g. counterbalance } with double-acting springs, e.g. for closing and opening or checking and closing {no material}