This standard applies to common window types such as casement windows (inward or outward opening), top-hung windows, and bottom-hung windows.
The lock cylinder is the core of anti-theft security and directly determines the lock's protection level. Among residential lock cylinders, C-grade lock cylinders currently offer the highest security and the longest resistance to technical unlocking, making them the preferred choice for families emphasizing theft prevention.
floor spring is a "door closer" hidden within the floor. It not only controls opening and closing but also allows adjustment of the closing speed and force. It holds the door steadily in place, preventing it from swinging uncontrollably in the wind.
Complies with the technical requirements of the national standard GB/T 37267-2018 "General Technical Conditions for Seismic Bracing and Hanging Systems in Buildings". The seismic bracing systems undergo comprehensive testing, including appearance, dimensions and tolerances, coating thickness, load-bearing performance of seismic connecting components, load-bearing performance of pipeline connecting components, cyclic loading performance, fatigue performance, fire resistance, and corrosion resistance.
<p>the sequential door closer ensures the doors close in the "right order," while the door closer ensures they "close properly." Understanding their differences is key to selecting the right components that meet safety standards while enhancing usability.for reliable door control hardware, consider 3H Hardware</p>
LTD811
3H INC.
Item No. | LTD811 |
Size | 51*39*20-30mm |
Application | Sliding door and sliding window |
Material | 304 stainless steel + Nylon Wheels |
Surface Treatment | Natural |
Color | Natural |
Load Bearing | 40/54 KG/pair |
Function | durable,easy-installation,smooth-operation |
Package | Box |
Specification

Product Description
1. Comply with JG/T 129-2017 Construction Door and Window Hardware- Roller
2. Door rollers work well after 100,000 cycles tested with its biggest capacity.Window rollers work well after tests of 25,000 cycles tested with its biggest capacity.
How to Install the Roller?
a).The connection of the roller and the sash is different due to the difference of the roller and profile.
Decide the way of the installation first,then use the screw or bolt accordingly.
b).The roller and the bottom of the sash must be firmly connected.
Item No. | LTD811 |
Size | 51*39*20-30mm |
Application | Sliding door and sliding window |
Material | 304 stainless steel + Nylon Wheels |
Surface Treatment | Natural |
Color | Natural |
Load Bearing | 40/54 KG/pair |
Function | durable,easy-installation,smooth-operation |
Package | Box |
Specification

Product Description
1. Comply with JG/T 129-2017 Construction Door and Window Hardware- Roller
2. Door rollers work well after 100,000 cycles tested with its biggest capacity.Window rollers work well after tests of 25,000 cycles tested with its biggest capacity.
How to Install the Roller?
a).The connection of the roller and the sash is different due to the difference of the roller and profile.
Decide the way of the installation first,then use the screw or bolt accordingly.
b).The roller and the bottom of the sash must be firmly connected.
