Emtek LC4-PAS28B 28 Degree Rotation Latch, Passage Function

Both. The LC4-PAS28B is an adjustable-backset tubular latch that sets to either 2-3/8 or 2-3/4 inches, which are the two standard residential backsets, so you don't have to measure the existing prep before ordering. It's also stocked as a fixed choice: you pick 2-3/8 or 2-3/4 as the backset option, in either a brass or chrome nose bolt finish.

If the door is bored to the standard 2-1/8 inch cross bore, yes. The LC4-PAS28B is built for a 2-1/8 inch cross bore and a 1-3/8 to 1-3/4 inch door, so it goes into an existing prep without redrilling. Thicker doors than 1-3/4 inches are out of range for it.

No. It's a passage latch only, non-keyed, with no locking function, so it suits hall and closet doors where the knob or lever just turns. For a bed or bath door that needs a thumbturn, or an exterior door that needs a key, you need the privacy or keyed latch instead. The Deltana DLP23875 drive-in latch is a passage/privacy latch with the same adjustable 2-3/8 or 2-3/4 backset, and the Deltana DLE23875 is the entry-function version.

The rotation figure describes how far the latch tailpiece turns to retract the bolt, and it has to match the lockset driving it. The LC4-PAS28B is the 28 degree version, so pair it with the Emtek passage knob or lever that calls for 28 degree rotation. A latch with a different rotation will bind or fail to fully retract even though it drops into the same 2-1/8 inch cross bore.

The Deltana DLP23875 is the closest cross-brand match. Like the LC4-PAS28B, it is an adjustable-backset latch set for 2-3/8 inch or 2-3/4 inch and it serves passage function, the Deltana being rated passage/privacy so it also works behind a privacy set. The Emtek unit is a 28 degree rotation latch with a brass body and comes with a round or square corner faceplate, and it fits doors 1-3/8 inch through 1-3/4 inch; the Deltana DLP23875 covers 1-3/8 inch through 2 inch. Both are non-keyed, so either drops behind a knob or lever with no cylinder.

The Emtek LC4-PAS28B is a passage latch, non-keyed, so it has no provision for a keyed entry set. For a keyed opening, the Deltana DLE23875 is an adjustable entry latch covering doors 1-3/8 inch to 2 inch. Same tubular family of prep, different function: entry rather than passage, which is what a locking exterior or unit door calls for.

The Emtek LC4-PAS28B is built for doors 1-3/8 inch to 1-3/4 inch. For a heavier slab, the Deltana DLP23875 passage/privacy latch is specified for doors 1-3/8 inch to 2 inch and shares the same adjustable 2-3/8 inch or 2-3/4 inch backset, so the bore layout on the door does not change.

The LC4-PAS28B is a residential-duty brass passage latch. For a rated opening, the Kwikset 83521 RCAL plain latch is built to a UL 3 hour rating and suits BBL, KNL, CNL and PLL trim, and the Kwikset 83518 RCAL adjustable square drive latch is likewise UL 3 hour. Confirm the trim on the door matches the Kwikset series before ordering, since those latches are keyed to that trim family rather than to Emtek.

The faceplate on the LC4-PAS28B comes round or square corner, and it should match the mortise already cut into the door edge. A square corner plate covers a routed square pocket; a round corner plate suits a prep cut with a hole saw jig. Getting it wrong means chiseling the edge or leaving a gap.

It's a residential-duty part. The LC4-PAS28B is a brass passage latch in Emtek's residential line, meant for interior doors in homes and light multi-family use rather than high-cycle commercial openings. For a school, hospital, or office corridor, spec a commercial tubular or cylindrical lock latch instead.

Tubular. It goes into a bored door with a 2-1/8 inch cross bore and a latch hole through the edge, not into a routed mortise pocket for a mortise lock body. If your door has a rectangular mortise cut in the edge for a full lock case, this is not the part.

They are not interchangeable on backset. The Kwikset 84290 is a square corner plainlatch built to a fixed 2-3/8 inch backset, so it only suits a door bored at 2-3/8 inches. The Emtek LC4-PAS28B adjusts between 2-3/8 inch and 2-3/4 inch and is offered with a round or square corner faceplate, which is what lets one part number cover both common bore layouts across a set of doors. The LC4-PAS28B is also the latch matched to the 28 degree rotation of the Emtek passage trim it is built for, so swapping in a generic plain latch changes how the knob or lever throws.

The prep in the edge of the door is what separates them. The LC4-PAS28B carries a faceplate, supplied round corner or square corner, so the door edge is mortised to receive that plate and the plate is screwed off. The Deltana DLP23875 is a drive-in latch, meaning the collar seats into the bored edge hole without a mortised faceplate. Both are adjustable to a 2-3/8 inch or 2-3/4 inch backset, so the choice follows how the door edge is already machined rather than the bore itself.

The LC4-PAS28B is a passage latch, non-keyed and with no locking provision, so it is for doors that only need to latch closed. For an opening that needs a privacy turn, the Deltana DLP23875 is rated passage/privacy on the same adjustable 2-3/8 inch or 2-3/4 inch backset, so it covers both duties from one part number.

Only the nose bolt shows once the door is closed, and it comes in brass or chrome. Pick the one closest to your knob or lever finish if the edge of the door is visible; the faceplate and strike do the rest of the visual work. For a fleet of interior doors, ordering all one nose bolt finish keeps the openings consistent.