Click image to view full size image
FEATURES
? UL listed floor spring, ANSI/BHMA 156.4 Grade 1 Certification
? Two-speed adjustment, closing smoothly.
? Slim square box design, easy installation
? 2,000,000cycles tested by Intertek
? Applicable for glass door, wooden door, aluminum door and frame door
? Different Cam for Optional (Germany, Italy, Brazil, Japan and so on)
link:https://www.heinda-cn.com/floor-spring/single-cylinder-floor-spring/high-quality-single-cylinder-floor-spring.html
High Quality Single Cylinder Floor Spring