What is the difference between SDS-plus and SDS-Max

SDS is the name for a drill bit shank system that allows quick and easy replacement of drill bits in drills.

We distinguish two main types of SDS shank. The SDS-plus (SDS+) shank has a diameter of 10 mm and is usually found on drills up to a diameter of 30 mm. Larger drills already have an SDS-Max shank, which has a diameter of 18 mm.

The SDS-plus and SDS-Max shank systems differ mainly in their use, size and compatibility:

SDS-plus

• Used in smaller and medium-sized rotary hammers (usually up to 5 kg).

• The diameter of the drill shank is 10 mm.

• It has four flutes - two open for clamping and two closed for better guidance.

• Designed for drilling into concrete and masonry, but with a limitation in the diameter of the drilled holes (usually up to 30 mm).

SDS-Max

• Used in larger, more powerful hammers and drills (usually over 5 kg).

• The diameter of the drill shank is 18 mm.

• It has five flutes - three open and two closed for better stability and power transfer.

• Suitable for larger and deeper holes (usually over 30 mm) and heavy demolition work

In short: SDS-plus is for smaller and lighter tools, while SDS-Max is for larger hammers with higher power and larger drill bits.

SDS-plus drill bits are usually used for drill bits up to 30 mm in diameter. For larger drill bits, the SDS-Max shank (18 mm shank diameter) is already intended and these are used for more complex drilling with heavy hammer drills/demolition hammers.

The designation of the clamping of drills or chisels in pneumatic hammers and the tools in power tools comes from the abbreviation for Special Direct System (SDS; originally Steck, Dreh, Sitzt – insert, turn, hold). The clamping system of drilling and chiseling tools in pneumatic hammers was developed by Robert Bosch.