Backer-On #9 x 1-1/4 in. Star Drive Serrated Head Cement Board Screws (185-Pack)

Serrated head design for flush seating even at an angle
Star drive with T-25 bit provides StikfitTM for easy 1-handed installation and eliminates cam-outs
Serrated thread forms require less torque for faster installation
Patented sharp point offers immediate pick-up and eliminates the need to pre-drill
Patented design allows attaching close to edge on cement board, reducing fractures or blow outs
Premium corrosion resistant finish
Use to attach cement board to wood or light gauge steel studs
Conforms to ANSI A108.11 standards for cement board attachment