Durable extruded aluminium construction. Automatic locking buttons. E-graduation 1cm on front and mm scale on back. Soft nylon carry case. Extends from 1.22m to 5m. For use with optical levels (including Silverline 633665). Durable extruded aluminium construction. Automatic locking buttons. E-graduation 1cm on front and mm scale on back. Soft nylon carry case. Extends from 1.22m to 5m. For use with optical levels (including Silverline 633665).