A3600 Series

The American Lock A3600 Series is a line of solid brass, door key compatible padlocks built around a single premise: one key should work both your door lock and your padlock. Most padlocks sold at hardware stores use a proprietary cylinder format that can never be keyed to match a building's door hardware. The A3600 solves that problem at the lock body level by accepting 9 different types of common Key-In-Knob (KIK) and padlock cylinders, including Schlage C, Kwikset, Yale, Medeco, ASSA, LSDA, and other aftermarket cylinders. The result is a padlock that can be added to an existing keying system without changing any door hardware or creating a separate key for the padlock. American Locksets stocks the full A3600 Series as an authorized American Lock dealer, with same-day shipping and free shipping on all orders over $300.

 American Lock A3600 Series Solid Brass Door Key Compatible Padlocks

 The A3600 Series body is 1-3/4 inch (44mm) wide by 3/4 inch thick solid brass. Brass as a body material is not an aesthetic choice here. It is a functional specification. Solid brass resists corrosion in outdoor environments, coastal applications, chemical storage areas, and any setting where steel-bodied locks would oxidize and seize over time. The brass body handles the corrosion resistance duty while the boron alloy shackle handles the cut resistance requirement. That division of material roles across the lock body vs. shackle is what makes the A3600 effective across a wide range of environments.

 The dual ball bearing locking mechanism secures the shackle from both sides of the heel and toe when closed. This two-point retention resists prying and pulling attacks that defeat single-ball-bearing designs. Combined with the hardened boron alloy shackle, the A3600 resists the physical attack methods that defeat standard brass padlocks at a lower price point.

Three Models: A3650, A3651, A3652 by Shackle Length

 The A3600 Series covers three distinct shackle length configurations, each suited to different clearance requirements.

American Lock A3650: 1-1/8 Inch Short Shackle

The A3650 is the standard hasp and gate lock configuration. The 1-1/8 inch (28mm) tall, 5/16 inch (8mm) diameter hardened boron alloy shackle provides maximum resistance against bolt cutters and cold chisels because the short exposed shackle length gives an attacker very little leverage surface to work with. This is the correct shackle length for most commercial door hasps, utility enclosures, and storage units where the clearance between the hasp and the body is tight. It is also available without cylinder for facilities that source cylinders separately or need to match an existing key system before ordering.

American Lock A3651: 2 Inch Medium Shackle

The A3651 uses a 2 inch (51mm) shackle length on the same 1-3/4 inch solid brass body. The additional clearance accommodates thicker hasps, chain links, and applications where the A3650 short shackle doesn't reach through the mounting hardware. Chain attachments, outdoor equipment storage, and gate hardware with wider hasp profiles typically call for this shackle length. The A3651 WO version ships without a cylinder for custom cylinder configurations.

American Lock A3652: 3 Inch Long Shackle

The A3652 extends the shackle to 3 inches (75mm), with the same 5/16 inch (8mm) diameter and hardened boron alloy material. Long shackle configurations are specified for chain-through applications, oversized hasps on heavy-duty gate hardware, and outdoor equipment where the lock must pass through a larger loop or cable eye. The A3652 WO version is available without a cylinder.

Why the 9-Cylinder System Matters for Commercial and Institutional Buyers

The A3600's ability to accept 9 different cylinder types solves a real operational problem in buildings where padlocks and door locks are maintained by the same facilities team. Standard padlocks require a separate key from the door locks, which multiplies the key count for every employee or contractor who needs access to multiple secured areas. When the padlock uses the same Schlage C, Kwikset, Yale, or other cylinder as the door hardware, the same key works both. This isn't just a convenience. It directly affects key control, audit trail accountability, and the cost of rekeying after a lost key event.

The A3600 Series also accommodates lockout/tagout (LOTO) applications in industrial environments where compliance requires individual padlocks per employee, each keyed differently, but the facility's master key system must still work across all of them. The 27 available keyway options and compatibility with American Lock's Edge key control cylinders make that level of key management achievable with a single padlock model across a facility.

Quick-Change Shackle and Key Retaining Options

The A3600 Series quick-change shackle allows the shackle to be replaced in the field without disassembling the lock body. For facilities that run high cycle counts on padlock applications, shackle wear is typically what ends a padlock's service life, not the body or cylinder. Being able to swap the shackle without replacing the entire lock or rekeying reduces long-term maintenance cost.

The key-retaining function can also be changed without disassembling the lock. Standard configuration is non-key-retaining (NKR), meaning the key can be removed with the shackle in either the open or closed position. The non-removable key (NRK) option holds the key in the lock until the shackle is fully closed, which prevents keys from being left in unlocked padlocks. This function change is field-adjustable, not factory-only.

American Locksets: Authorized American Lock Dealer Since 2001

American Locksets has stocked American Lock commercial padlocks as an authorized dealer since 2001. We carry the A3600 Series across all three shackle lengths and cylinder configurations, including the WO (without cylinder) versions for facilities that source cylinders separately. 

Browse all American Lock padlocks, the full American Lock product catalog, and explore all padlocks and builder's hardware stocked at American Locksets. Same-day shipping and free shipping on orders over $300 apply across the A3600 Series.

Frequently Asked Question

Q: What is the American Lock A3600 Series?

 The A3600 is a solid brass, door key compatible padlock series that accepts 9 cylinder types so one key works both your padlock and door hardware.

Q: What is the difference between the A3650, A3651, and A3652?

 Shackle length only. The A3650 has a 1-1/8 inch shackle, the A3651 has 2 inches, and the A3652 has 3 inches. The body is identical across all three.

Q: What cylinders are compatible with the A3600 Series? 

Compatible cylinders include:

• Schlage C keyway

• Yale 8 keyway

• Kwikset

• Medeco

• ASSA

• LSDA

Additional aftermarket and American Lock Edge key control cylinders are also available. 

Q: What does WO mean on the A3650WO, A3651WO, and A3652WO? 

WO stands for "without cylinder." The lock body ships without a pre-installed cylinder so you can add your own to match an existing key system.

Q: Is the A3600 Series suitable for outdoor use? 

Yes. The solid brass body provides excellent corrosion resistance. The hardened boron alloy shackle resists both cutting and rust in wet or coastal environments.