Professional 1/2" drive ratchet adaptor with 20 gear teeth, cold-forged from special alloy steel with induction heat treatment. Meets ASME B107.10 standards with 18-degree swing arc for superior durability and reliability.
The Snap-on 1/2" Drive Ratchet Adaptor (Model S77A) is a professional-grade tool engineered for demanding industrial applications. This cold-forged adaptor is manufactured from special alloy steel and induction heat-treated to deliver superior performance and exceptional durability. With 20 gear teeth and an 18-degree swing arc, this adaptor provides smooth, reliable operation for precision work in aviation, aerospace, military, defense, oil and gas, power generation, railroads, and general industry applications. The chrome-finished head measures 3 inches in width and 1-5/8 inches in depth, while the total length is 3 inches, making it ideal for both standard and confined workspace applications.
Designed to meet ASME® B107.10 standards, this ratchet adaptor ensures compliance with industry regulations and guarantees reliability in critical work environments. The 1/2-inch square drive design is compatible with standard ratchet systems and provides versatile connectivity options. The adaptor's precision engineering and robust construction make it an essential component for professional technicians and maintenance teams across multiple industries. Whether used in aviation maintenance, heavy-duty fleet servicing, or general industrial repair work, this adaptor delivers consistent performance and longevity.
Snap-on's commitment to quality is evident in every aspect of this ratchet adaptor. The special alloy steel construction combined with induction heat treatment ensures maximum strength and resistance to wear and corrosion. The adaptor is backed by Snap-on's reputation for excellence and comes with a repair kit (RKRS77) for extended service life. This is a must-have tool for any professional mechanic or maintenance technician requiring reliable, durable adaptor solutions.
Key Features
- Cold forged from special alloy steel for maximum strength and durability
- Induction heat-treated for superior performance and extended service life
- 20 gear teeth with 18-degree swing arc for smooth, reliable operation
- Meets ASME B107.10 international standards for professional applications
- Chrome finish for corrosion resistance and professional appearance
- 1/2-inch square drive design compatible with standard ratchet systems
- Precision-engineered dimensions for both standard and confined workspaces
- Includes repair kit (RKRS77) for extended tool longevity
- Ideal for aviation, aerospace, military, oil and gas, and industrial maintenance
- Professional-grade construction backed by Snap-on quality assurance
Technical Specifications
| Specification |
Value |
| Model Number | S77A |
| Square Drive Size | 1/2 inch |
| Gear Teeth | 20 |
| Swing Arc | 18 degrees |
| Head Width (Dimension B) | 3 inches |
| Head Depth (Dimension A) | 1-5/8 inches |
| Overall Length (Dimension C) | 3 inches |
| Material | Special alloy steel, cold forged |
| Heat Treatment | Induction heat-treated |
| Finish | Chrome |
| Standards Compliance | ASME B107.10, ANSI |
| Repair Kit | RKRS77 |
| Joint Repair Kit | Not applicable |
| Replacement Coverplate | Not applicable |
| Replacement Grip | Not applicable |
| Locking Mechanism Repair Kit | Not applicable |
