The 213 Shutterbolt from Brio is a unique flush bolt designed for external, aluminium shutters. Its default position is throw bolt extended so when the panel slides across the opening, the throw will find and locate with holes drilled in the bottom channel. The easy lift handle retracts the throw bolt and allows panels to slide into desired positions, but if a panel is left in an unlocked position and caught by a strong gust, the shutter will travel to the next hole and safely self lock.