Rockwood 900 Heavy Duty Magnetic Catch

Both. The 900 heavy duty magnetic catch works on a single door or on a pair of doors, and it ships with the strikes to cover either case: one long 5/8 x 3-1/8 inch strike and two short 5/8 x 1-1/8 inch strikes in the box. On a pair, the long strike gives you more forgiveness where the two leaves meet; on a single door the short strike is usually all you need.

It is certified to ANSI A156.9 under type number B03161, which is the BHMA standard covering cabinet and auxiliary door hardware. That is the line a spec writer or an institutional buyer wants on the submittal for a school, hospital, or government building. The 900 is a commercial grade catch, not a residential cabinet catch.

That is exactly what the 900 is for. It mounts at the head or the meeting point and holds the inactive leaf closed magnetically, and the self-aligning triple-pole magnets mean the leaf does not have to land perfectly to grab. Use the long 5/8 x 3-1/8 inch strike on that application: the extra length gives the magnet a target even when the door is settling slightly off position. Note that this holds a door shut, it does not latch or lock it, so it will not secure an opening on its own.

Fasteners are included for both halves: two #6 x 1-1/4 inch truss head sheet metal screws for the catch body and two #6 x 1/2 inch flat head sheet metal screws for the strike. Installation instructions are in the box too. Those are sheet metal screws, so for a hollow metal frame or a solid wood door or jamb you can drive them straight; on anything hollow or on a substrate that will not hold a #6 SMS you will need to supply your own anchors.

A magnetic catch like the Rockwood 900 holds the door closed with magnetic pull rather than spring tension on a roller, so there is no wear part to compress out and no click when the door pulls free. The 900 uses dual triple-pole self-aligning magnets, which is what lets it grab even when the leaf is not landing perfectly square, a common problem on an aging pair of doors. It is certified to ANSI A156.9 for commercial use. Where you need positive mechanical latching, a magnet is the wrong choice and you want a real latch instead.

All three strikes ship in the box with the catch: one 5/8 x 3-1/8 inch and two 5/8 x 1-1/8 inch, plus the mounting screws for both the body and the strike. Nothing on the strike side has to be ordered separately, and the two short strikes mean you have a spare on a single door application.

A magnetic catch such as the Rockwood 900 or the Trimco 810 Series holds a door closed by magnetic pull against a steel strike; it is not a latching device and does not secure an opening. The Rockwood 900 uses dual triple-pole self-aligning magnets, which is what lets it grab a slightly out-of-alignment leaf, and it is a commercial-duty part. Use it on cabinet doors, closet and utility doors, and inactive leaves that need to stay shut but not locked. If the opening needs to resist forced entry, hold a fire rating, or accept a key, a magnetic catch of either brand is the wrong part and a latch or lockset belongs in the door instead.

Two: natural aluminum (ALM) and brass. The catch body is aluminum substrate. On most commercial jobs the natural aluminum blends with aluminum frames and mill finish trim; brass is the one to pick when you are matching brass or bronze hardware on the rest of the opening.