CL250-4 120° Compact Concealed Adjustable Hinge — Steel (White Zinc Plated) / SUS304 (Ground Finish)
Full Technical Specifications
- Model Numbers: CL250-4 (Steel) / CL250-4B (SUS304)
- Overall Dimensions: 60mm total height × 14.5mm width (mounting plate)
- Maximum Opening Angle: 120°
- Material Options:
- CL250-4: Carbon steel
- CL250-4B: SUS304 stainless steel
- Surface Finish:
- CL250-4: White zinc plating (rust-proof, wear-resistant)
- CL250-4B: Precision grinding (satin metallic, corrosion-resistant)
- Pivot Pin Diameter: Φ5mm
- Adjustable Mounting Plate: 14.5mm width × 60mm height, slotted holes (12mm length), 42mm hole spacing
- Side Profile Dimensions: 32.5mm depth, >39mm clearance, 24.5mm total height, <16mm barrel diameter, door panel thickness t=3mm, frame thickness 2.5mm
- Core Features: Compact concealed hidden installation, slotted plate for positional adjustment

Core Product Features & Advantages
2.1 Compact Concealed Hidden Installation for Seamless Aesthetics
The hinge is designed to be completely concealed within the cabinet door-frame gap when the door is closed, with no visible hardware on the exterior. With a compact 60mm height and 14.5mm mounting plate width, it is ideal for small and medium-sized equipment enclosures where installation space is limited, creating a clean, seamless and premium professional appearance.
2.2 Slotted Adjustable Mounting Plate for Precise Door Alignment
The innovative slotted mounting plate allows for fine positional adjustment during and after installation, enabling installers to achieve perfect door alignment, consistent gap spacing and smooth operation. This adjustability compensates for minor sheet metal fabrication tolerances and ensures a professional fit even on compact cabinet assemblies.
2.3 Dual Material Options for Versatile Application Requirements
Two material variants are available to match different environmental and budget needs: the CL250-4 carbon steel version with white zinc plating offers cost-effective rust protection for standard indoor industrial applications, while the CL250-4B SUS304 stainless steel version with precision grinding finish delivers superior corrosion resistance, salt spray endurance and a premium satin appearance for outdoor, coastal and harsh-environment installations.
2.4 Controlled 120° Opening Angle with Φ5 Pivot Pin
The 120-degree maximum opening angle is engineered to provide sufficient access for internal operations while preventing the door from over-rotating and colliding with adjacent equipment, walls or operators. The Φ5 solid steel pivot pin ensures tight assembly clearance, low-friction rotation and high wear resistance for smooth, wobble-free operation over tens of thousands of open-close cycles.
2.5 Secure Slotted Screw Mounting
The adjustable mounting plate features two slotted holes (12mm length each) with 42mm center spacing, allowing both secure fixation and positional fine-tuning. This slotted design provides flexibility during installation while maintaining robust and stable performance, resisting loosening from vibration and mechanical impact.
2.6 Space-Saving Profile with Generous Depth Clearance
With a 60mm height, 14.5mm width and 32.5mm depth profile, this hinge fits neatly within small cabinet door-frame recesses. The >39mm internal clearance, 24.5mm side height and <16mm barrel diameter, combined with compatibility for t=3mm door panels and 2.5mm frame thickness, cover common compact sheet metal cabinet configurations.
Application Fields
- Small electrical control boxes, compact PLC enclosures, terminal junction boxes and low-voltage distribution cabinets
- Laboratory portable testing instruments, miniature medical diagnostic devices and analytical equipment housings
- Communication equipment cabinets, indoor server boxes and compact signal transfer enclosures (SUS304 version for outdoor)
- Automation equipment protective covers, industrial test fixtures and small actuator housings
- Medical equipment casings, environmental monitoring devices and electronic instrument panels
- Food processing equipment, stainless steel sanitary cabinets and cleanroom facility enclosures (SUS304 version)
- Outdoor monitoring equipment, weather-resistant instrument panels and small coastal equipment enclosures (SUS304 version)
- Premium compact furniture, electronic equipment casings and decorative enclosures where hidden hinges are preferred
Installation & Maintenance Guidelines
Step-by-Step Installation Procedures
- Determine the installation positions on both the cabinet frame and door panel according to the dimension drawing
- On the cabinet frame: align the hinge body and mark the mounting positions
- On the door panel: align the adjustable slotted mounting plate and mark the mounting positions, then loosely fasten with screws through the slotted holes
- Close the door and adjust the position via the slotted plate to achieve perfect alignment and consistent gap spacing
- Once aligned, fully tighten all mounting screws on the adjustable plate
- Test the 120° opening movement for smooth rotation and verify door alignment
- Confirm that the hinge is completely concealed when the door is closed and operates without binding
Installation Quantity Recommendation
- Door height ≤400mm: Install 2 hinges symmetrically
- Door height 400mm to 700mm or medium-weight steel door: Install 3 hinges for balanced load distribution
Maintenance Instructions
- Steel version (CL250-4): suitable for indoor dry environments; not recommended for long-term outdoor exposure, high-humidity areas or coastal salt spray
- SUS304 version (CL250-4B): suitable for both indoor and outdoor environments, including damp, coastal and mildly corrosive conditions
- Wipe the surface periodically with a soft dry cloth to remove dust, grease and moisture; for SUS304 version, avoid abrasive cleaners that may scratch the ground finish
- Apply a small amount of dry lubricant to the Φ5 pivot pin every six months to maintain smooth and quiet rotation
- Check mounting screw tightness quarterly, especially on equipment subject to continuous vibration
- Re-check door alignment and gap consistency annually; readjust via the slotted plate if necessary
- Inspect the surface treatment annually for chips or scratches; touch up with matching paint or zinc-rich coating if necessary
Product Summary
CL250-4 is a compact 120° concealed adjustable hinge available in carbon steel (white zinc plated) or SUS304 stainless steel (precision ground finish). Its space-saving hidden installation design, slotted adjustable mounting plate for precise door alignment, Φ5 pivot pin and dual material options make it a premium and versatile hardware solution for small electrical cabinets, compact automation equipment enclosures, medical instruments, outdoor installations and various industrial applications requiring a clean concealed appearance combined with accurate door fitment in limited space.
CL250-4 steel SUS304 compact concealed adjustable hinge 120 degree white zinc plated grinding finish slotted holes Φ5 pin small industrial cabinet equipment hinge





