Simplex pushbutton lock, model 1041B 26D. Supplied less the Best-type IC Cylinder - must purchase separate. This lock will accept the Best compatible interchangable cores (not included) - purchase separately. UNICAN 1000 Series locksets are the best for limiting access to high-traffic, security-sensitive areas in commercial, institutional, and industrial buildings. Ideal for locations with a high personnnel turnover rate, such as processing centers, employee entrances, hospitals, and R&D labs. Supplied with key override feature (cylinder not provided), and optional passage feature on side trim.