Kaba Ilco Jimmy Proof Locks, Single Cylinder

Prep for a 2-1/2 inch backset with a 1-1/4 inch crossbore. Note that 2-1/2 inches is not either of the standard bored-lock backsets of 2-3/8 or 2-3/4 inches, so if you are replacing a knob or standard deadbolt the hole will not line up. On a door already carrying an older jimmyproof rim lock, the 2-1/2 inch backset and 1-1/4 inch crossbore are the common vertical-deadbolt prep and the cylinder hole usually reuses.

KW1. If your building is already keyed in KW1, which covers the bulk of residential and light commercial keying, the cylinder can be keyed alike to the rest of your doors by a locksmith. If your property runs a different keyway, order the less-cylinder version and fit a rim cylinder in your own keyway instead.

Four ways to order it. Box Pack and Clam Shell Pack are the same lock in different packaging, clam shell being the retail hanging card and box pack the trade carton, which matters if you are buying by the case for a building. Less Cylinder - Box Pack ships without the rim cylinder so you supply your own in your building's keyway. Less Cylinder - Flat Strike - Box Pack does the same and swaps the strike to the flat pattern for a flush jamb rather than a rabbeted one.

A jimmyproof lock mounts on the surface of the door and interlocks two vertical bolts into a strike screwed to the jamb, so the bolts have to be sheared rather than pried apart. That interlock is the reason it stays the standard choice on inswing apartment and multi-family doors, where a spread jamb defeats a horizontal bolt. A conventional deadbolt bores through the door and throws sideways into the frame, which needs a solid jamb and a good strike to resist prying. If you are working with old, soft, or out-of-square jambs, the jimmyproof is the more forgiving retrofit because it does not depend on the frame holding the bolt.

Single cylinder, so it is keyed from the outside and operated by a turn knob on the inside. That is the configuration most jurisdictions require for a dwelling unit egress door, since nobody needs a key to get out. If the door has glass within reach of the lock, a double cylinder version is what you would look for instead.

The flat strike. Ilco offers a Less Cylinder - Flat Strike - Box Pack for exactly that condition, where the jamb face is flush with the door edge and the standard angled or rabbeted strike will not seat. On a wood jamb with a rabbet, the strike supplied with the regular box pack or clam shell is the one you want.

No handing to specify. A jimmyproof mounts on the inside face of the door with the strike on the jamb, and the vertical bolts engage the same way regardless of which side the hinges are on. What does matter is that it is for an inswing door, since the lock body and strike both sit on the interior. Order the same part for left hand and right hand openings.

Mostly surface mount, but there is one hole to bore. The lock case screws to the interior face of the door and the strike screws to the jamb, so there is no mortise and no edge prep. The only through-bore is the 1-1/4 inch crossbore for the rim cylinder, set at a 2-1/2 inch backset. If you are pulling an existing jimmyproof off the door, that cylinder hole is normally already there.

It is rated commercial, and it is a common spec on multi-family and light commercial entries, back-of-house doors, and storage rooms. The function is entry, keyed outside with an inside turn. For a heavy-traffic main entrance on an outswing or aluminum storefront door, a jimmyproof is the wrong tool, since it needs an inswing door with a solid interior face to mount to.