Features and Benefits:

• Radius corner design extends the life of fasteners; design drives the side of the fastener instead of the corner
• Design also avoids rounding of rusted or damaged fasteners
• Designed to tackle the toughest jobs with solid durability and keeps them pounding job after job
• Black oxide finish and has etchings for identification

This is a 3/8 in. Female x 1/4 in. Male Adapter. It is 3/8 in. drive. Re-engineered to dramatically increase durability. Forged from the finest chrome-molybdenum alloy steel, the best choice for strength.