MK means the lock is supplied keyed different and master keyed, so each padlock has its own change key while a master key opens the group. The cylinder is rekeyable, so a locksmith can pin it to an existing system rather than living with the factory keying. That is what makes it workable for a property manager or facilities crew who wants one master to cover every gate, cage and truck box in the building.

For cut and pry attack, yes. A hidden shackle lock like the A801LHC buries the shackle inside a 2-7/8 inch body so there is nothing exposed for bolt cutters or a pry bar to grab, but it only works with a matching hidden shackle hasp. A conventional shackle padlock goes on almost anything (chain, standard hasp, gate latch) at the cost of an exposed shackle. If you need the flexible option instead, the Sargent 858 is a non-key-retaining padlock with a stainless steel shackle, and the Schlage KS23D/KS23F is a brass padlock with a 5/16 inch shackle.

The A801LHC is a hidden shackle design with a 3/8 inch shackle diameter, a 1-9/32 inch shackle length and a 2-7/8 inch body width, so the shackle sits recessed inside the body and is shielded once the lock is closed on a matching hasp or hockey-puck style mount. The Sargent 858 is a conventional padlock with an exposed stainless steel shackle and a US4 satin brass finish, which drops onto any standard hasp or chain without special mounting hardware. Choose the hidden shackle when the opening has a shrouded hasp and you want the shackle out of reach of cutters; choose the open shackle when the lock has to pass through a chain, a gate loop, or a conventional staple.

The A801LHC is a rekeyable padlock, keyed different and master keyed, so the cylinder is serviced by rekeying rather than by swapping a core. If your facility standardizes on removable cores, the Sargent 60-858-2 is a removable core padlock with a 2 inch stainless steel shackle, which lets you pull and replace the core when tenants or staff change without pulling the lock off the hasp. Note that it is an open shackle body, so it will not drop into a shrouded hidden-shackle hasp the way the A801LHC does.

The A801LHC ships keyed different and master keyed, so each lock carries its own change key while a single master operates the group, and the cylinder can be rekeyed later as the program changes. The Sargent 82-856 is a non-key retaining padlock on the KESO system with a 2 inch by 2 inch brass case and a stainless steel shackle, and the Medeco 5260 is a 52 Series brass body padlock with a 7/16 inch shackle diameter using M3 key technology in satin chrome. The deciding factor is usually which keyway your property is already pinned to, since the padlocks should fall into the same hierarchy as the door cylinders rather than becoming a second key ring.

The A801LHC is the padlock only. A hidden shackle lock is useless on its own, so you order the matching hidden shackle hasp separately and size it to the lock: 2-7/8 inch body, 3/8 inch shackle diameter, 1-23/32 inch shackle width. On a roll-up door or gate, also plan the weld or through-bolt hardware for mounting the hasp.

No. The A801LHC is a keyed, master keyed security padlock for hasps and gates, not a lockout/tagout device. For LOTO you want a lightweight, non-conductive or aluminum safety padlock: the ABUS 72/30 anodized aluminum safety padlock (1-1/4 inch body, 3/16 inch shackle), the ABUS 74/40 insulated safety padlock with a 6-pin cylinder, or the ABUS 76/40 plastic-covered aluminum core lock.

Not directly. The A801LHC uses a rekeyable pinned cylinder that a locksmith repins to your system, rather than accepting a removable core. If you standardize on IC and want to swap cores rather than repin, the Sargent 60-858-2 is a removable core padlock with a 2 inch stainless steel shackle. It is a conventional shackle lock though, so it will not drop into a hidden shackle hasp.

As supplied, the A801LHCMK is keyed different with a master key over the group, so every lock has its own key. Because the cylinder is rekeyable, a locksmith can pin a batch keyed alike if you want one key per crew or per building section. Decide that before you deploy them, since repinning a carton of six after the fact is labor you do not need to buy.

No. The ABUS 72/30 is an anodized aluminum safety padlock with a 1-1/4 inch body width and a 3/16 inch shackle diameter, built light for lockout/tagout tagging on equipment. The A801LHC is a commercial hidden shackle lock with a 2-7/8 inch body and a 3/8 inch shackle. If you are locking a roll-up door, trailer or gate hasp, the 72/30 is the wrong tool; if you are locking out a disconnect or valve for worker safety, the 72/30 or the insulated ABUS 74/40 with its 6-pin cylinder and 1/4 inch shackle is what you want.

The A801LHC is a silver-finish commercial padlock whose hidden shackle design keeps the shackle enclosed in the body when locked. For an opening where standing water and salt are the main concern, the Medeco 521 G8R is a weather-tight padlock with a solid stainless steel body, supplied less the pop-out cylinder, and the Medeco 54515G XT is an indoor/outdoor electronic padlock with a 5/16 inch shackle diameter, non-key retaining, supplied with cylinder. The G8R keeps a mechanical key; the XT brings audit and scheduling to a remote gate where you would otherwise be issuing brass.

The Schlage KS23D/KS23F is a brass padlock with a 5/16 inch diameter shackle, and the Sargent 758 is a key retaining standard padlock in a US4 satin brass finish. Both are conventional open-shackle bodies that hang on any common hasp or chain. The A801LHC differs in that its 3/8 inch shackle is recessed into a 2-7/8 inch wide body, which requires a mating shrouded hasp but leaves almost nothing for a bolt cutter to grab. The Sargent 758 is also key retaining, meaning the key cannot be withdrawn while the lock is open, which matters if you do not want keys left in open locks on a jobsite.

Commercial. It is classed as a commercial padlock and sold in master cartons of 6, which is how these move for multi-door and multi-gate jobs rather than one-off residential use.

The A801LHC is a silver-finish commercial padlock and the enclosed body shields the shackle from direct weather and attack, but no corrosion or weather-sealing spec is carried for it. If you are putting locks in a marine or washdown environment, the Medeco 521 G8R is a weather-tight padlock with a solid stainless steel body, and the ABUS T84MB/30 Nautic is a sleeved lock built for that duty.

Not for the same duty. The ABUS 76/40 is a plastic-covered aluminum core padlock with a 1/4 inch shackle diameter and a 1 37/64 inch width, and the ABUS T84MB/30 Nautic has a black sleeve with a 13/64 inch shackle diameter and a 1 17/64 inch body width. Both are small-bodied locks for lockers, cabinets, and light marine or utility use. The A801LHC is a commercial-duty lock with a 3/8 inch shackle and a 2-7/8 inch body designed to mate with a shrouded hasp. Specify the ABUS bodies where the staple is small and the risk is casual; specify the A801LHC where the hasp is rated and the shackle needs to be out of reach.