The Prime‑Line U 9970 Single Cylinder Deadlock provides dependable surface‑mounted door security for homeowners seeking proven protection against forced entry. Constructed from durable diecast metal with a corrosion‑resistant brass‑colored finish this jimmy‑resistant lock is designed to help secure hinged doors by preventing the spreading and prying of door frames. Featuring a surface‑mounted cross bolt locking mechanism the U 9970 helps anchor the door to the jamb for enhanced resistance against physical attack. The keyed single cylinder design includes a tamper‑resistant shutter guard to help deter lock tampering and picking. Designed for use on wood, metal or resin doors 1-3/8 to 2-3/8 inch thick, this deadlock installs easily using the included mounting hardware and standard household tools making it a practical choice for DIY installation. Each set includes the deadlock, flat keeper, 2 keys and installation components for a complete and reliable door security solution.