Tekton TRQ52403 - 1/2 in. 300 ft-lb Micrometer Torque Wrench

Most torque wrenches in a hangar top out at 200 ft-lb. For the majority of aircraft fasteners, that is enough. But there is a category of work — turboprop and turbofan engine mount hardware, heavy aircraft main landing gear trunnion fasteners, rotorcraft transmission attachment bolts, propeller hub retention on high-displacement engines — where the AMM calls for 250, 275, or 300 ft-lb not as an outlier but as the specified value. The Tekton TRQ52403 is the 1/2 inch drive micrometer torque wrench built for that work: 40–300 ft-lb, calibrated to ISO 6789 across the full stated range, with a serialized certificate of calibration documenting the actual measured accuracy of your specific tool.

There is a mechanical reality worth understanding at this torque level: the internal spring of a micrometer wrench is under maximum compression every time you work near 300 ft-lb. Calibration drift at the top of the range develops faster than at mid-scale, and an under-torqued primary structural fastener carries consequences that a loose panel screw does not. This is the class of tool where a documented, scheduled recertification program is not overhead — it is risk management. Pilot John International is an ISO 17025-accredited calibration laboratory that can recertify your TRQ52403 and issue a NIST-traceable certificate accepted by FAA Part 145 repair stations, Part 91/135 operators, and AS9100 quality systems. One distributor, one accredited lab, for the life of the tool.

Key Features

• 40–300 ft-lb Range — Reaches the turboprop mount, heavy landing gear, and rotorcraft drive system fastener values that a 200 ft-lb wrench cannot; the top of the Tekton micrometer line
• ISO 6789 Full-Range Calibration — Tested from 40 ft-lb to 300 ft-lb in both directions; five readings per set point; exceeds ASME B107.300 at every requirement
• ±3% Accuracy CW & CCW — Actual measured accuracy of your individual wrench on the serialized certificate — not a model average
• 1 ft-lb Minimum Increment — Resolution that matters at 300 ft-lb, where over-torque is as structurally damaging as under-torque
• 90-Tooth Fixed Ratchet Head — Single half-moon pawl holds 9 teeth engaged simultaneously; 4° swing arc; engineered not to skip under high-torque load
• Dual-Direction Click Mechanism — Positive audible and tactile confirmation in both clockwise and counterclockwise directions
• Locking Collar — Auto-locks between fasteners; critical on high-torque sequences where accidental over-setting causes structural damage
• Laser-Etched Micrometer Scale — Satin finish, high-contrast bold fonts, straight centered indicator lines; readable at a glance on the large fasteners this wrench services
• Coarse Diamond-Knurl Grip — Deep-cut pattern with centerline groove; engineered for two-handed leverage at 300 ft-lb without losing pivot-point discipline
• HDPE Carrying Case — Hard-shell, custom-fit; protects wrench and certificate between workstations
• Lifetime Warranty — No receipts, no time limits; Tekton makes it right

Specifications

• Drive Size: 1/2 in.
• Torque Range: 40–300 ft-lb
• Calibration Standard: ISO 6789
• Accuracy: ±3% clockwise and counterclockwise
• Minimum Increment: 1 ft-lb
• Ratchet Teeth: 90
• Swing Arc: 4° per tooth
• Head Style: Fixed
• Mechanism: Micrometer click-type
• Scale Units: ft-lb (single-unit scale)
• Handle Finish: Satin
• Case Material: HDPE (latches: polypropylene)
• Certificate: Serialized, included
• Warranty: Lifetime

ISO 17025 Calibration for High-Torque Tools — Because 300 ft-lb Drift Is Not a Minor Issue

Pilot John International is an ISO 17025-accredited calibration laboratory. High-torque micrometer wrenches used regularly near their maximum range are candidates for more frequent recertification than lower-range tools — the mechanical demands at 300 ft-lb accelerate internal wear in ways that are not externally visible. PJi can establish a usage-appropriate recertification schedule for your TRQ52403, issuing NIST-traceable certificates accepted by FAA Part 145 repair stations, Part 91/135 operators, EASA-regulated MROs, and AS9100 / ISO 9001 quality programs. We maintain your calibration history so your tool control log is always current and audit-ready. No other aviation tool distributor selling this wrench can make that offer.