When organisations require maximum intrusion resistance and flexibility in a master key system, they choose 4KS.


maximum security master key system

SCEC Approved includes SL3 Rated Products and patented to 2035 master key system that utilises a springless design, making 4KS very unique.

The key is reversible meaning it can be inserted either way making
operation simple. The 4-curve design incorporates additional security
ensuring the system is suitable for deployment in the largest and
most complex master key systems. Unlike most master key systems
that rely on spring pressure in the cylinder, the 4KS sliders (locking
pins) inside the cylinders are actively moved by the tracks in the
key. This active operation means 4KS will outperform all others in
challenging environments be they dirty, dusty or salty.

National network

EVVA 4KS is available through a national dealer network. The
network consists of a select group of locksmith companies that have
met the strict dealership appointment criteria.​

UNTIL 2035





When it comes to performance in challenging environments, the active sliders and springless design in 4KS provides an edge that is unmatched by other systems. As a key is inserted, most master key systems rely on small springs to push the locking pins into place. Even small amounts of dust,
dirt or grit can affect the operation of the cylinder. Thanks to the 4KS springless design, when the key is inserted into the cylinder, the sliders (locking pins) are actively moved into place by the tracks of the 4KS key. This provides industry leading operation and
reliability in the harshest of environments.

High strength keys

Key breakage is a very common problem with some master key systems. This can be caused for many reasons, such as the key material being too soft or deep cuts in the key located at critical leverage points (which means the key is easily damaged by the user). The 4KS key is manufactured from high grade nickel silver and is extremely difficult to damage or break. The unique design ensures the key is not weakened regardless of the location of the cuts.

Complex structure

Not all master key systems have the ability to create a hierarchy of keys to suit the requirements of very large sites. 4KS is designed to provide a highly complex multi-level master key system that can be scaled for future expansion as needed.


one key
many features

As a reversible key with unique rounded tip, the 4KS key is simple to use. The high-quality nickel-silver alloy of the key, the teflon coating of all locking elements and the springless technology of the 4KS cylinder guarantee high wear resistance even under the toughest conditions. The special feature of the 4KS key is the overlapping curve technology. It practically rules out all forms of manipulation within the locking system and the use of dealer profiles greatly enhances security.

The original 4KS key is produced exclusively by EVVA to increase system security. Distribution of the key blanks is tightly controlled with keys only available through certified dealers of EVVA 4KS.


The unique technology of 4KS offers three different levels of protection against key reproduction, illegal key copies and manipulation:

01. Increased security through EVVA dealer network
02. Technical protection
03. Legal protection

one cylinder
many details

4KS is patented, springless and anything but conventional. In contrast to other locking systems, the locking elements in the 4KS cylinder are sliding along the tracks of the key. Minimal force is needed to insert the key due to lack of spring resistance. A total of 12 springless locking pins are brought into specific positions via active placement of the 6 curve millings on the key and are scanned via 2 control bars. A locking bar in the cylinder controls the key’s additional coding. The 4KS key is scanned a total of four times before a cylinder can be opened, offering the highest security. The combination of a nickel-silver cylinder and carbide components instead of brass is why 4KS locks have been cycle-tested to 100,000 operations. 4KS cylinders are available in a wide variety to suit almost all common Australian and New Zealand locks.



Impressioning is a covert method of producing a functioning key. Impressioning relies on marks being left on a blank key that are then filed to produce a key. Due to the frictionless design of 4KS this is virtually impossible.


Bumping is a method of covert manipulation to open a cylinder and relies on spring pressure to work when
inserting a specially cut key. Due to the unique 4KS design, making a bump key is virtually impossible. Furthermore,
the key blanks distribution is very tightly controlled.


The control bars within the cylinder are anti drill. The sliders (locking pins) are made from carbide. There are also additional anti drill pins strategically placed in the cylinder to increase drill resistance.


4KS is virtually pick proof. This is because of the complexity of the 12 sliders alignment with not one locking element (shear line) but three.