CDI 802MFRFMHSS – 3/8" Flex Head Torque Wrench

The CDI 802MFRFMHSS is a 3/8-inch drive, single-scale micrometer click-type torque wrench covering 10–80 ft-lb (13.6–108.5 Nm) with one capability the rest of the CDI foot-pound family doesn't have: a flex head that pivots ±15 degrees in both directions. That pivot exists to solve a specific and persistent problem in aviation engine maintenance — reaching fasteners that are physically accessible but not wrench-accessible because a fixed-head ratchet can't generate a full torque arc in the space the engine bay provides.

The problem this wrench solves

Every A&P knows the failure mode: socket on the fastener, but the wrench body hits the cowl rail, a wire bundle, a tube cluster, or an adjacent component before the handle has enough arc to generate and confirm torque. You reach for a ratchet without documentation, pull the cowl further than the job requires, or accept that the torque application is approximate. The 802MFRFMHSS eliminates that failure mode. With the head pivoted off-axis up to ±15°, the handle swings in the space that's available while the socket stays seated on the fastener — full, documented, calibrated torque in a space that would otherwise require a workaround.

Documentation-ready for certificated maintenance

Every 802MFRFMHSS ships individually serialized with a NIST-traceable certificate of calibration, satisfying traceability requirements in FAA-accepted maintenance programs, Part 145 repair station QCMs, and ISO 9001 quality systems. Meets or exceeds ASME B107.14 and ISO 6789. Accuracy: ±4% CW, ±6% CCW of indicated value from 20–100% of full scale.

Built for the confined-space fasteners other wrenches can't reach

• Flex head pivots ±15° in both directions — the only flex-head wrench in the CDI micrometer adjustable lineup
• 3/8" drive, 10–80 ft-lb (13.6–108.5 Nm) in 0.5 ft-lb increments — fine resolution for engine accessory hardware
• Single scale English ft-lb — clean, readable in confined access spaces without the visual complexity of dual scale
• Knurled metal handle with spring-loaded pull-down lock ring for positive setting retention
• Audible click plus tactile impulse confirms torque even when the click position is out of direct sightline
• Extension handle included — extends reach into deep engine bays and behind firewall-mounted components
• Packed in a metal storage box for protection between use in environments where tools take knocks
• 16.60" overall length keeps the handle outside most confined spaces while the flex head works inside
• Made in the USA by CDI Torque Products, a Snap-on Industrial Brands company

Where A&P mechanics reach for the 802MFRFMHSS instead of a fixed-head wrench

• Oil filter adapter mounting hardware on Continental and Lycoming engines (20–40 ft-lb) — typically blocked by the sump or a baffled cowl
• Fuel injection servo and carburetor attach bolts on engine mounts with restricted forward access
• Exhaust stack flange hardware and exhaust port studs behind adjacent cylinders
• Heat muff clamp hardware on exhaust systems where the heater box blocks straight wrench access
• Alternator and vacuum pump mounting bolts on the back of the accessory case where tube bundles obstruct the handle arc
• Magneto and ignition harness hold-down hardware in tight forward engine locations
• Firewall-adjacent hardware where the fixed head would contact the firewall before completing the torque arc

Why source aviation tooling from Pilot John International

Pilot John International is an aviation-specialist distributor — not a general industrial catalog. We serve Part 145 repair stations, FBOs, MRO operations, and flight schools across the U.S. The 802MFRFMHSS is the wrench that turns a ratchet workaround into a documented torque application — and that documentation matters in a Part 145 QCM review. Our on-site ISO 17025-accredited calibration laboratory recertifies it and returns it with a current NIST-traceable certificate, keeping the confined-space work on your aircraft defensible under audit.</