10Pcs PH2 Screwdriver Bits Set (PH2x150)

That is a different problem from the countersink case a 100mm bit solves. Here the screw itself is long, and by the time it is nearly home the driver has travelled a long way in with it. A shorter bit runs out of shank and the chuck arrives at the surface before the screw is seated, which is how the last few turns get done at an angle or not at all. A 150mm bit keeps the driver clear right to the end of a long fixing.

It also suits driving into the back of a carcase, through a frame, or into a fixing that sits behind a rail or a bracket.

The trade is flex. At 150mm the shank twists measurably under torque and will wander if the driver is not held square, and on a long screw there is a lot of turning to do — so any misalignment gets many chances to cam the bit out. Line up on the axis, start slowly, keep firm pressure straight down it, and let the screw pull itself in rather than forcing.

The steel is S2 industrial at HRC 58-62. S2 is shock-resisting, which is what allows that hardness on a bit that is spun, cammed and hammered — and on a longer shank the toughness half of the balance matters especially, since a brittle bit of this proportion would snap rather than flex.

Satin finished, ten to a pack.

The buyers are carpenters and framing joiners, drylining and insulation contractors, kitchen and wardrobe installers, shopfitters, roofing and cladding contractors, and hardware dealers supplying construction.

Replace the bit once the flutes show rounding — a worn tip rounds every screw it touches, and the wear is gradual enough to pass unnoticed. Message us on WhatsApp for a price.