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Cylinders – Master Lock’s Ten Basic

Cylinders – Master Lock’s Ten Basic

In the last few blogs we have shared information on Keying Options and three types of Tumbler Locks. The last blog also touched on the Master Lock innovation that brought us the EDGE™ Key Control System. To be more specific, the patented Master Lock innovation made to the Pin Tumbler Cylinder to provide a heightened level of security. Now we are going to continue with more on Lock Cylinders.


Let us start with the cylinder itself. A lock cylinder is a small cylindrical housing that contains the locking mechanism allowing for keyed access to the locking device. The cylinder lock has some unique advantages over other locks.

The first, and possibly most important, is that a cylinder can be removed. This makes it much easier for rekeying or changing out the cylinder entirely. Another advantage is that many lock cylinder manufacturers make cylinders that are compatible with other locking devices and other manufacturers’ keys and keyways. This is important for Master Keyed Lock Systems that may already be in place, such as matching an existing door key to custom built padlocks.

There are a few different types of lock cylinders: Rim Cylinders, Mortise Cylinders, Cylindrical Lock or Tubular Deadbolts Cylinders

As promised, we will be discussing the Master Lock Company basic cylinders for padlocks.

Master Lock Company makes ten basic cylinder sizes/types for use in our padlocks;

1. A small diameter cylinder for some of our laminated locks.

2. A four pin cylinder for our laminated locks.

3. A five pin cylinder for our laminated rekeyable locks

4. A six pin cylinder for our ProSeries® locks.

5. A cylinder for our number 19 lock.

6. SFIC small format interchangeable core cylinders.

7. Cylinders compatible with various door hardware locks made by others.

8. Master Lock EDGE™ System

9. Python®

10. Universal Pin

1. The small diameter cylinder, or the number W7, is common to the Master Lock Number 7 laminated padlock. The number W7 cylinder is claimed as “generally not accessible for rekeying”(p 13), or simply Non-Rekeyable to help prevent lock picking.

2. The four pin cylinder, number W1, is used with Master Lock’s Number 1, 3 and 5 laminated padlocks as well as other Master Lock products.  The number 1, 3 and 5 padlocks are all commercial grade featuring superior protection from drilling and prying for both the locking mechanism and locking devise. The W1 cylinder also has an available extension so that the four pin cylinder can be adapted to a 5 pin lock. When ordered, the number 1, 3 and 5 padlocks are all non-rekeyable.

3. The five pin cylinder, number W27, is used in the Master Lock number 21, 24, 25 and 27 laminated rekeyable locks. These padlocks are also commercial grade, however, the odd numbers are laminated steel, and the even number 24 is laminated brass. The different metals are best suited for different security applications, but that is a topic for another day. The advantage of the rekeyable number W27 five pin cylinder is that it can be rekeyed.

4. The six pin cylinder can have two different part numbers, depending on how many pins are used. Pay attention because this part gets a little confusing, if the six pin cylinder uses all six pins the part number is W7000; but if it is pinned with just five pins it is number W6000. This/these cylinders are common to the Master Lock ProSeries® padlocks. The ProSeries® padlocks have additional options for weather tough and high security applications where the cylinder W7000 or W6000 could be pinned to match your existing key system.

Quick note: The above four Master Lock cylinders use the Master Lock #291 pinning kit.

5. The cylinder for a Master Lock number 19 lock, the number W19, is fairly permanent unless you drill out the rivets. Not one of the easier cylinders to rekey, playing up to the higher level of security for the number 19; but it is possible to rekey or replace the number W19 cylinder.

Editors note: The general consensus here is that the number 19 was discontinued.


6. SFIC can be deceptive for those not familiar with the lock industry. A simple acronym, Small Format Interchangeable Core, which should not be confused with IC or I/C, or standard Interchangeable Core cylinders.  Master Lock’s SFICs are available with 6 or 7 pins and are compatible with certain Best, Arrow and Master Lock keyways.

7. Door hardware cylinders can be one of the most important locking mechanisms because they protect you, your family, your stuff and your home or your business. Fortunately, Master Lock can provide cylinders compatible with select keyways from the following manufacturers: Arrow, Corbin, Harloc, Kwikset, Lockwood, Lori, Loricentric, Master/Dexter, Russwin, Sargent, Schlage, Segal, Weiser/falcon, Weslock, Yale, Master Lock EDGE™ System. Be sure to check specific compatibility or consult a professional before purchasing.


8. The Master Lock EDGE™ System available with 4 or 6 pinned cylinders was touched on briefly in the last blog. These cylinders are also compatible with the American Lock EDGE™ Padlock and Door Key Control System. For more information on the Master Lock EDGE™ Key Control System please click.

9. The Python® cylinder, which uses the disc tumbler mechanism, comes with the number 1 Keyway. Yet this crafty lock has a removable plug allowing rekeying and is Master Lock recommended, “that [the Python® cylinder] can be used in an increasing range of our automotive related products.” (p 16)

10. The Universal Pin cylinder (UP) is unique with respect to the pins. The Universal Pin cylinder is manufactured with undivided serrated pins, a top and bottom pin in one. The advantage of the serrated single solid pins is that the cylinder itself is Uncombinated (UN), a previously unmentioned keying option. Meaning that it can be matched to your existing key, permitting there is not excessive ware to your key, with the Master Lock 376 keying tool; instead of having to pin the cylinder.

Let me reiterate the importance of first knowing the use for a lock so that you can make the best decision for the job. This will not just provide the necessary level of security required of the lock, but also ensure longevity with proper maintenance and upkeep to maximize the lifetime of the lock. With a little extra reading you might be able to replace your own cylinders, however, we do recommend consulting a professional Locksmith.

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