Klimas expansion plug with countersunk cross head 6x35 KRX 3.5x35 – metal/plastic fastener

Klimas expansion plug KRX 6x35 (3.5x35) is a mechanical anchor designed for fixing fittings, profiles and light fixtures in common building substrates such as concrete, solid brick and hollow block. The fastener combines a metal countersunk cross head with a plastic expansion body sized 6x35 mm and accepts M3.5 screws to provide a compact, low-profile connection for applications where a flush head is required.

Advantages

The combination of a metal countersunk Phillips head and a plastic expansion sleeve delivers reliable load transfer and corrosion resistance at the visible connection point while allowing controlled expansion in drilled holes. The 6x35 mm body provides sufficient embedment depth for light to medium loads in solid and hollow substrates, and the design supports quick installation with standard M3.5 screws. Overall, the fastener offers a balance of strength, neat appearance and compatibility with common construction screws.

Suitable for

• Fixing light fittings and electrical boxes to concrete and brick
• Mounting aluminium or PVC profiles and small hardware
• Securing fixtures in hollow block and aerated concrete with appropriate drilling
• Interior and semi-exterior installations where a countersunk finish is required

Key specifications

• Expansion body diameter: 6 mm
• Overall body length: 35 mm
• Compatible screw diameter: 3.5 mm (M3.5)
• Head type: countersunk cross (Phillips) metal head
• Materials: plastic expansion sleeve with metal head

How to use

Drill a hole of the correct diameter (6 mm) to the required depth in the base material, ensuring the drill bit and drilling method match the substrate. Insert the expansion plug into the hole until the countersunk head sits flush with the surface. Place the fixture or profile over the head, then drive an appropriate M3.5 screw into the plug until the sleeve expands and the connection is secure. Avoid over-tightening to prevent deformation of the expansion body or damage to the substrate.

Usage recommendations

Use proper drill bits for the substrate—masonry bits for concrete and solid brick, and appropriate hollow-wall drilling technique for blocks. For heavy loads or safety-critical installations, select anchors rated for the specific load and substrate or consult technical guidance. Store fasteners in a dry environment to maintain condition of the metal head and plastic sleeve.