The #9 x 2 1/2 Simpson Strong-Drive® WSV SUBFLOOR Screw T25 6-Lobe (Collated) offers superior performance, with a reduced diameter compared to other collated screws. The T25 6-Lobe drive and thread design provide maximum holding power with minimal installation torque, making it perfect for subfloor applications. The box of 1500 screws offers high-volume jobsite efficiency.