Gerda PRO System cylinder (WKM4) 35g/30 brass knob, class 6 D, box

GERDA Pro System Anti-Burglary Cylinder ? Unparalleled Door Security

The GERDA Pro System anti-burglary cylinder is a high-security lock insert designed for mortise locks, providing superior protection against intruders. This anti-bumping and anti-drilling cylinder safeguards your home with unwavering reliability. The GERDA WKM4 cylinder, tested by the Institute of Precision Mechanics in Warsaw according to PN-EN 1303:2015-07, achieved the highest classification: 1 6 0 B 0 C 6 D. The GERDA Pro System cylinder is approved for use in fire and smoke-resistant doors. GERDA Pro System cylinders are available in satin nickel and brass finishes, and with knob, thumbturn (WKM4), and gear (WKM4Z) options.

• Cylinder classification according to PN-EN 1303:2015-07: 1 6 0 B 0 C 6 D


• Certified by the Institute of Precision Mechanics


• Exceptional mechanism durability ? 6 locking pins, over 100,000 cycles


• Over 2,700,000 key code combinations


• Highest security class ? 6


• Highest burglary resistance ? Class C (high) according to KT/402/IMP/2014


• Superior corrosion and temperature resistance (-20/+80 degrees Celsius) ? Class C (highest)


• Attack resistance: Class D ? highest (5/10 min. drill resistance, high resistance to mechanical attacks)


• Recommended for fire doors


• Anti-drilling protection (internal cylinder protected by a hardened steel plate)


• Anti-picking protection (two additional top latches)


• Anti-picking pins prevent unwanted opening via bumping techniques


• Additional anti-burglary locking bolt


• New double-diameter pins


• Includes 5 high-security keys, a key code card, screw, and attractive packaging.

How to choose the right cylinder size?

Watch the video below.

Valued Customers, Please Choose Carefully

We are committed to your satisfaction and the highest safety standards. All our certified cylinder locks are packaged in sealed boxes to guarantee their integrity and full functionality.

Due to the product's nature, please note that we cannot accept returns of opened or damaged packages, as these products cannot be resold.

Please carefully review the technical specifications and precisely measure your door dimensions before purchasing. If you have any questions or concerns, our team is ready to assist you in selecting the right product.

Thank you for your understanding and we invite you to explore our offerings.