Arrow MK01 - Grade 2 Passage Cylindrical Lock

The Arrow MK01 is a Grade 2 passage cylindrical knob lock, a knob set with no locking mechanism, just a latch that lets the door open and close from either side at all times. The passage function (ANSI F75) means the knob always retracts the latch on both sides, there's no key, no button, and no way to lock it. It's the knob set you use on doors that need to latch shut but never need to be secured, closets, corridors, supply rooms, and pairs that just need to stay closed against a stop. The MK01 is part of Arrow's MK Series, a value-focused Grade 2 line for commercial doors where heavy-duty Grade 1 hardware isn't required, and the latch is reversible so one unit fits any door.

What the passage function does

This is worth being clear on, because passage means no security at all. Turn the knob on either side and the latch retracts so the door opens, release it and the spring latch holds the door closed against the frame. There's no locking, no key, no privacy button, nothing to secure the door. That's exactly the point on a closet, a stockroom that doesn't need locking, a hallway door, or one leaf of a pair, you want reliable latching with free operation from both sides, never the risk of locking someone in or out. If you need the door to lock, the MK Series offers other functions (the MK02 for privacy, the MK12 for storeroom, the MK17 for classroom), but the MK01 is the pure passage knob.

Because the latch is reversible, the MK01 fits left-hand and right-hand doors without specifying handling, which keeps ordering and stocking simple.

Built for commercial doors at a Grade 2 value

The MK01 is built to ANSI/BHMA Grade 2, the right level for commercial openings that see normal traffic and don't need Grade 1 strength. The lock chassis is cold rolled steel with a zinc dichromate finish for corrosion resistance, and the latch housing is steel with the same finish, durable, practical construction for everyday commercial use. It fits a standard 2-1/8" cross bore with a 7/8" edge bore, doors 1-3/8" to 1-3/4" thick, and a 2-3/8" backset standard (with 2-3/4", 3-3/4", and 5" available). The brass latch has a 1/2" throw.

You can specify the MK01 with a choice of knob styles, Ball (BD), Tudor (TA), or Darrin (DD), in eight architectural finishes from bright brass to satin chrome, so it matches the rest of the building's hardware. A UL-listed backset option is available for fire door applications.

Arrow MK01 specifications

• Function: Passage (ANSI F75). Latch operated by knob from either side at all times. No locking, no key.

• Grade: ANSI/BHMA Grade 2. Handling reversible.

• Knob styles: Ball (BD), Tudor (TA), Darrin (DD).

• Chassis: Cold rolled steel, zinc dichromate finish for corrosion resistance.

• Bore: Standard 2-1/8" cross bore, 7/8" edge bore.

• Backset: 2-3/8" standard. 2-3/4", 3-3/4", 5" available. UL backset option available.

• Door thickness: 1-3/8" to 1-3/4".

• Latch: Brass, 1/2" throw, steel housing with zinc dichromate finish.

• Strike: Brass, bronze, or stainless. Standard T strike 2-3/4" x 1-1/8"; optional ANSI A115.1 strike 4-7/8" x 1-1/4".

• Finishes: 8 (605/US3, 606/US4, 609/US5, 612/US10, 613/US10B, 619/US15, 625/US26, 626/US26D).

• Warranty: 3-year limited.

Why choose the Arrow MK01

Arrow (an Assa Abloy brand) builds dependable commercial hardware, and the MK Series gives architects, contractors, and facilities a clean, accessible, value-priced Grade 2 option where Grade 1 isn't needed. The MK01 passage knob is the simple, durable choice for any door that just needs to latch and operate freely, no locking. With reversible handling, multiple knob styles, eight finishes, and a UL option, it fits a wide range of commercial openings while keeping the spec straightforward.

One thing to confirm before ordering: passage means no locking at all. If the door ever needs to lock, choose a different MK function (MK02 privacy, MK12 storeroom, MK17 classroom). Select your knob style, finish, and backset to match your doors.

Order the Arrow MK01 from American Locksets

We stock the full Arrow MK Series from authorized distribution, so every lock ships with the manufacturer warranty. Compare functions and finishes in the Arrow MK Series category, see all Arrow knob locks, or browse all commercial locks.