Emtek LC4-PRV28B 28 Degree Rotation Latch, Privacy Function

Yes. The LC4-PRV28B is a tubular latch built for a 2-1/8 inch cross bore, which is the standard prep on residential doors, and the backset adjusts between 2-3/8 and 2-3/4 inches so it drops into either of the two common edge bores. Door thickness range is 1-3/8 to 1-3/4 inches. If your door is already bored for a knob or lever, no new drilling is needed.

No. It is a residential privacy latch, non-keyed, for bed and bath openings. For a fire door application, Kwikset's 84290 square corner plainlatch with a 2-3/8 inch backset and the 83521 RCAL plain latch are UL 3 hour latches.

It matters. The 28 degree rotation refers to how far the spindle turns to retract the latch, and it has to match the knob or lever mechanism it is driving. The LC4-PRV28B is the 28 degree privacy version, non-keyed, for bed and bath doors where the inside turn locks and there is no cylinder. Pairing a rotation the trim was not built for leaves the latch under- or over-driven.

The nearest cross-brand match is the Deltana DLP23875, a drive-in latch with an adjustable 2-3/8 inch or 2-3/4 inch backset in a passage/privacy function. It lines up with the Emtek LC4-PRV28B on the two things that decide the bore: the same adjustable 2-3/8 inch or 2-3/4 inch backset and a non-keyed privacy/bed/bath function. The difference to plan around is the faceplate. The LC4-PRV28B ships as a faceplate latch with round or square corner and a brass body, while the Deltana DLP23875 is a drive-in design that seats in the edge bore without a mortised faceplate. If the door is already mortised for a corner faceplate, the Emtek drops into that prep; if you are boring fresh or the old prep is a plain drive-in hole, the Deltana suits it.

The LC4-PRV28B covers doors 1-3/8 inch to 1-3/4 inch thick. For a full 2 inch door in the same non-keyed privacy application, the Deltana DLP23875 is the one to spec: it is a passage/privacy drive-in latch with a door thickness range of 1-3/8 inch to 2 inch and the same adjustable 2-3/8 inch or 2-3/4 inch backset. This matters most on solid-core and older millwork doors in multi-family and hospitality stock, where slab thickness varies door to door. Measure the slab before ordering rather than assuming the fleet is uniform.

Both. The latch adjusts between the two backsets, and the ordering options are still split by backset (2-3/8 inch or 2-3/4 inch) and by nose bolt finish, brass or chrome. Measure from the door edge to the center of the 2-1/8 inch bore: 2-3/8 inches is typical on interior residential doors, 2-3/4 on heavier or exterior-style prep. Pick the finish to match the visible latch face on the door edge.

Both corner styles are covered. The LC4-PRV28B latch faceplate is supplied round or square corner, so it can be dropped into an existing mortised faceplate pocket either way, which matters on a retrofit where you do not want to rechisel the door edge. Match whichever shape is already routed into the door.

Inside only. It is a non-keyed privacy latch for bed and bath doors, with no cylinder and no key. If you need a keyed entry latch instead, the Deltana DLE23875 drive-in latch is an adjustable entry-function latch covering 1-3/8 to 2 inch doors.

If the units run Emtek knobsets or leversets on the bedroom and bath doors, yes, the LC4-PRV28B is the replacement privacy latch for the 28 degree rotation mechanism. It is sold as a replacement part on its own, not as a complete lockset, so the knob, lever, and rosettes stay on the door. Standardizing on one backset across the fleet keeps the ordering simple: check whether the doors are bored at 2-3/8 or 2-3/4 inches before committing to a quantity.

No. The Deltana DLE23875 is an adjustable drive-in latch in an entry function, while the LC4-PRV28B is a privacy/bed/bath latch and is non-keyed. Entry and privacy latches serve different sides of the door: an entry latch is built to work with a keyed exterior lockset, and a privacy latch is built for a thumbturn-and-emergency-release bed or bath set. The part numbers look adjacent and both are adjustable drive-in-class latches, which is exactly how the wrong one gets ordered. For a bedroom or bathroom door replacement, stay with the privacy latch. The Deltana DLP23875 is the passage/privacy member of that same Deltana pair if you need a cross-brand option.

They are not interchangeable. The Kwikset 84290 is a square corner plainlatch at a fixed 2-3/8 inch backset, and the Kwikset 83521 RCAL plain latch is built for Kwikset BBL, KNL, CNL and PLL trim. The LC4-PRV28B is a brass 28 degree rotation latch matched to Emtek privacy trim, with an adjustable 2-3/8 inch or 2-3/4 inch backset. Rotation angle is the reason to be careful here: a latch is driven by the spindle and hub of the lockset it was built for, so a plain latch from another maker can install cleanly in the edge bore and still fail to retract fully with Emtek trim. If you are replacing a broken latch behind an Emtek knob or lever, order the Emtek latch. The Kwikset parts belong on Kwikset trim.

The LC4-PRV28B is a residential privacy latch. For a rated opening, the Kwikset 83521 RCAL plain latch and the Kwikset 83518 RCAL adjustable square drive latch are both UL 3 hour, and the 83518 carries an adjustable backset while the 83521 is a plain latch matched to Kwikset BBL, KNL, CNL and PLL trim. Corridor and stairwell doors in a rated wall assembly are where this comes up, and the rating belongs to the whole assembly, so the latch has to be paired with trim and a frame prep that carry the label too. Verify the door label before substituting any latch into a rated opening.

Brass. That is the latch body material, and the nose bolt is ordered in either a brass or chrome finish so the exposed face on the door edge matches the rest of the trim.