SDS-PLUS Round Shank Electric Hammer Drill Bits (6x110)

An ordinary drill grips a round shank in a three jaw chuck and squeezes it tight. That works for turning, but it is poor at hammering, because to hammer the bit must be free to move back and forth along its own axis, and a chuck clamped hard around it cannot allow that. So a hammer action chuck drill shakes the whole machine and the whole bit together, and in concrete it mostly polishes the hole.

SDS solves it differently. The shank has slots cut along it, and the chuck holds the bit by those slots rather than by friction. The bit is locked against turning but is deliberately free to slide a few millimetres in and out, and a piston inside the machine strikes the end of it directly. That is why an SDS drill goes through concrete that a hammer drill only wears at: the blow is landing on the bit, not on the tool holder.

One thing must be said plainly, because our catalogue line does not. The spec says these suit SDS or Max systems. They do not. This is SDS-PLUS, which is the smaller and far more common standard. SDS-MAX is a physically larger shank used on breakers and heavy rotary hammers, and the two are not interchangeable in either direction. Check which chuck your machine has before ordering.

Six millimetres is the everyday fixing size: plastic wall plugs carrying conduit and trunking, light fittings, brackets, curtain rails, cabinets, cable clips and shelving. At 110mm overall it is short, and short is genuinely better here, because a shorter bit wanders less and is easier to keep square. Remember that overall length is not hole depth, since a portion of the shank sits inside the chuck.

Buyers are electricians, air conditioning fitters, shopfitters, carpenters, maintenance men and hardware shops.

Message 94 77 111 8880 and tell us your machine if you are unsure about the shank. We deliver island-wide.