Prime-Line Single Cylinder Jimmy-Proof Deadlock, Brass, 1-3/8 to 2-3/8 in.

Price: $26.87
(as of Oct 02, 2026 00:17:02 UTC – Details)


Add dependable supplemental security to entry doors with the Prime-Line U 9970 Single Cylinder Deadlock. Designed for surface-mounted installation, this jimmy-resistant deadlock helps protect against forced entry by securing the door to the jamb and helping resist door frame spreading and prying. It is an effective security upgrade for homeowners seeking additional protection beyond standard locksets. Constructed from durable diecast metal with a corrosion-resistant brass-colored finish, this deadlock is built for long-lasting performance and an attractive appearance. The surface-mounted cross bolt locking mechanism provides enhanced door security, while the keyed single-cylinder design features a tamper-resistant shutter guard to help deter lock tampering and picking attempts. Compatible with wood, metal, and resin doors measuring 1-3/8 in. to 2-3/8 in. thick, this lock installs easily using common household tools and the included mounting hardware. Each package includes the deadlock, flat keeper, two keys, and installation components for a complete security solution. Compare door dimensions and installation requirements before purchasing to ensure proper fit.
Ideal Use: Adds supplemental security to entry doors by helping resist forced entry, prying, and door frame spreading
Dimensions & Compatibility: Fits wood, metal, and resin doors from 1-3/8 in. to 2-3/8 in. thick.
Materials & Components: Durable diecast metal construction with brass-colored finish; includes deadlock, flat keeper, mounting hardware, and 2 keys
Key Features: Jimmy-resistant cross bolt design secures the door to the jamb and includes a tamper-resistant shutter guard for added protection
Fit Guidance: Surface-mounted installation requires no door edge mortising; verify door thickness and mounting location before ordering
Customers find the deadlock works smoothly and offers outstanding value for money, while being sturdy and easy to install. The security features receive mixed feedback, with some customers feeling safe while others express concerns about potential jamming. The fit and hardware receive mixed reviews – while some say it fits perfectly, others report it doesn’t align properly, and the included screws are described as cheap. Durability is a concern, with several customers reporting it broke right away.