FASTSHIFTER Invisible C4 Decking Screw 4.5×60mm – 600 pcs

FASTSHIFTER Invisible C4 decking screws 4.5 × 60 mm fasten deck boards from the side of the board, into the edge, so that no screw head is visible on the finished surface. The result is a clean, uninterrupted deck — and no exposed heads for water to sit around.

The screws are carbon steel with a C4-class coating tested to 1500 hours salt spray, which puts them firmly in the outdoor, coastal and high-humidity category. This pack contains 600 pcs + 2 bits.

Key features

• Invisible fastening — driven through the board edge, nothing shows on top.
• Double thread — pulls the board hard down onto the joist and closes the joint without gaps.
• 1500 h salt spray, C4 coating — for humid, coastal and exposed sites.
• Self-drilling tip — reduces chipping and splitting at the board edge.
• Conical head — seats cleanly without damaging the timber.
• T15 drive — bits included in the pack.
• Flexible carbon steel — tolerates the board movement that outdoor timber always has.

Where it is used

• Timber and thermally modified decking where a clean surface is required.
• Roof terraces, balconies and pool decks with high visual standards.
• Barefoot areas, where no screw head should be exposed.
• Any deck built with a hidden-fastening tool.

FAQ

What does the 1500-hour salt spray rating mean? It is a standard accelerated corrosion test. 1500 hours places these screws in class C4 — suitable for humid, coastal and industrial atmospheres, not just sheltered gardens.

Why a double thread? The second thread pulls the board down onto the joist as the screw drives, closing the gap and stopping the movement that causes squeaking later.

Will it damage the board? No — the conical head and drilling tip are designed to enter the board edge cleanly, and the fixing stays invisible from above.

What wood is it suitable for? Both thermally modified and ordinary softwood decking, in outdoor conditions with moisture and temperature cycling.