The Series S4 by SYSTEM SÄLZER® is a steel security door built for the world’s most demanding security applications. Certified up to RC6, FB7-NS, and EXR5, this high-performance system is designed to withstand aggressive attacks, explosive blasts, fire exposure, and prolonged use in high-traffic areas.
Despite its robust specification, the S4 door is visually versatile — available in finishes such as stainless steel, timber cladding, and bronze. Its design excellence was recognised with the German Design Award, highlighting its rare combination of functionality and form.
Available in both inward and outward opening formats, and compatible with SYSTEM SÄLZER® facades and access systems, the S4 series is suitable for industrial plants, government buildings, and critical infrastructure. Custom glazing, louvers, fire-rated variants, and full automation capabilities ensure the door meets every specification — without compromise.