The Wheeler 38-Piece F.A.T. Wrench Screwdriver Set (MPN: 1237377 / WH-FWSS) provides handheld, repeatable torque control for firearm maintenance, optic mounting, and bench gunsmithing. Utilizing a mechanical spring-clutch mechanism, this manual driver allows users to apply precise tension across a range of 10 to 65 inch-pounds (in-lbs) in 1 in-lb increments, delivering an audible and tactile click once the set value is reached. The set includes hardened S2 tool steel bits (56–58 HRC) with a black phosphate corrosion-resistant coating, featuring hollow-ground flat bits specifically designed to seat squarely into firearm screw slots without slipping or marring fastener heads.

Key Features

• Adjustable Torque Range: Delivers precise mechanical torque from 10 to 65 in-lbs, adjustable in single in-lb increments.
• Certified Accuracy: Maintains an accuracy rating of ±2 in-lbs for settings up to 40 in-lbs, and ±5% for settings between 40 and 65 in-lbs.
• Standard Magnetic Interface: Features a standard 1/4" hex drive with a magnetized tip to secure bits during operation.
• Durable Bit Construction: Contains S2 tool steel bits hardened to 56–58 HRC with a protective black phosphate finish.
• Firearm-Specific Profiles: Includes hollow-ground flat bits with parallel edges engineered to prevent screw head deformation.
• All-In-One Storage: Supplied with 36 assorted driver bits/adapters, the torque handle, and a latching stackable hard storage case (38 pieces total).

Specifications

• Product: Wheeler 38-Piece F.A.T. Wrench Screwdriver Set
• MPN / Model: 1237377 / WH-FWSS
• Total Component Count: 38 pieces (1 torque driver, 36 bits/adapters, 1 hard case)
• Torque Capacity: 10 to 65 in-lbs
• Adjustment Increments: 1 in-lb
• Torque Accuracy: ±2 in-lbs (10 to 40 in-lbs); ±5% (40 to 65 in-lbs)
• Drive Size: Standard 1/4" hex drive
• Bit Hardness & Finish: 56–58 HRC S2 tool steel; black phosphate coating
• Power Requirements: Manual mechanical operation (no batteries or electrical power needed)

Who is the Wheeler Screwdriver Set Fat Wrench 38 Pce for?

• Precision rifle scope mounting — Delivers controlled tension across an adjustable 10 to 65 in-lb range with ±2 in-lbs accuracy up to 40 in-lbs, allowing shooters to fasten optic rings and bases to exact manufacturer torque specifications using this firearm torque screwdriver set.
• Bench gunsmithing and firearm maintenance — Provides 38 pieces total, including hollow-ground flat bits and standard 1/4" hex drive adapters, to service action screws, guard screws, and accessory rails without stripping or marring firearm fasteners.

Less suitable for: Applications involving ultra-delicate sub-10 in-lb micro-fasteners, which require a dedicated micro-torque screwdriver, or high-load fasteners exceeding 65 in-lbs (such as barrel nuts or heavy chassis bolts), which require a high-range foot-pound torque wrench.