The Necked Barrel Bolt needs to be twisted to be opened and is most commonly used on cupboard or shed doors - Suitable for indoor or outdoor use. - Corrosion resistant. - Can be installed horizontally or vertically. Barrel bolts are easy to fit and designed for security applications on lightweight doors, chests and cabinets. They can be used in a vertical, horizontal, left or right hand application. The necked versions are ideal for inside hallway cupboards and French doors.