The Borka Tools 4 Inch-Lbs Precision Torque Limiter is a specialized, fully mechanical hand tool engineered to prevent the over-tightening and stripping of delicate micro-fasteners. Factory pre-set to an exact slip threshold of 4 in-lbs, it incorporates an internal clockwise cam-over mechanism calibrated to ISO 6789 standards within a certified accuracy range of ±1% to ±2%. Measuring 0.87 inches in outer diameter by 3.0 inches in length and weighing 3.5 ounces, this compact all-metal torque limiter connects via a 3/8-inch square female input drive and standard 1/4-inch hex female output socket with magnetic bit retention for precise turret and zero-stop maintenance.

Key Features

• Calibrated 4 In-Lbs Slip Mechanism: Delivers precise clockwise cam-over action to prevent thread damage and internal mechanism crushing on micro-fasteners.
• Counter-Clockwise Protection: Features counter-clockwise torque limiting to safeguard internal factory calibration if accidentally turned in reverse.
• Standard Bit Compatibility: Equipped with a 1/4-inch hex output socket featuring magnetic retention alongside a 3/8-inch square input drive for manual ratchets or gear adapters.
• All-Metal Construction: Durable, non-powered mechanical build with individual serialization for calibration tracking.

Product Specifications

• Preset Torque Rating: 4 in-lbs (factory pre-set, non-adjustable)
• Calibration Accuracy: Certified within ±1% to ±2% (ISO 6789 standards)
• Outer Diameter: 0.87 inches (22.1 mm)
• Overall Length: 3.0 inches (76.2 mm)
• Weight: 3.5 ounces (~99 grams)
• Input Interface: 3/8-inch square female drive / knurled body manual grip
• Output Interface: 1/4-inch hex female drive with magnetic retention
• Operation Type: Manual hand operation only

Who is the Borka Tools 4 Inch-Lbs Precision Torque Limiter for?

• Precision rifle competitors servicing optic turrets — requires a dedicated precision torque limiter factory-calibrated to exactly 4 in-lbs to safely tighten micro elevation and windage turret set screws without crushing sensitive internal tracking components.
• Long-range shooters adjusting zero-stop set screws — utilizes a compact 3.5-ounce, 3.0-inch precision torque limiter to securely reset scope zero-stops in the field using an ISO 6789-calibrated slip mechanism accurate to within ±1% to ±2%.

Less suitable for: Fasteners requiring higher torque settings such as optic ring screws at 15–20 in-lbs or receiver action screws at 45–65 in-lbs, which require higher-rated preset torque limiters or multi-torque adjustable drivers; also unsuitable for use with motorized screwdrivers, drills, or power impact drivers, which will destroy the internal calibration mechanism.