The Hilti TE 4-A18 cordless rotary hammer drills anchor holes or through holes in concrete and masonry with an optimum drilling diameter range of 1/4 to 1/2 in. The CPC battery technology protects the battery, switch and motor. Drop-resistant housing and a high-efficiency motor are standard. A keyless "click" chuck allows for fast and easy drill bit changes and a variable speed trigger gives the operator more control in all drilling positions. The TE 4-A18 can be operated in hammer-drilling mode and drilling only mode.