M85049/49-12W Straight Cable Clamp Backshell for D38999 Circular Aerospace Connectors

The M85049/49-12W is a straight cable clamp backshell designed for circular electrical connectors. It is the AS85049 / GJB1784 standard part number, interchangeable with J1784/49-12W, and is commonly used with GJB599 / D38999 Series I and Series II connectors in shell size 12.

As an HB-type (industry designation HB-B12) accessory, the M85049/49-12W provides anti-rotation retention and straight-exit mechanical strain relief without EMI shielding braid termination. Tightening the clamp ring onto the grommet helps secure the cable and improve the connector's environmental resistance in tensioned-cable installations.

Product Features

• Conformant to national standard GJB1784 (equivalent to AS85049)
• Interchangeable with cross-reference part number J1784/49-12W
• Straight cable clamp backshell for axial cable exit and strain relief
• Anti-rotation design with clamp-ring sealing for improved environmental durability
• Suitable for crimp GJB599 Series I / II connectors where cable clamping without EMI shielding is required
• Cadmium plating finish denoted by the W suffix (olive drab)
• Shell size 12 for D38999 / GJB599 circular connector interfaces

Technical Specifications - M85049/49-12W

Part Number Breakdown

Related finish option: M85049/49-12N (HB-F12) uses electroless nickel finish. There is no functional difference between model prefixes marked "M85049" and related AS85049 designations.

Compatible Applications

The M85049/49-12W straight backshell is intended for aerospace, avionics, and industrial platforms that use D38999 / GJB599 circular connectors and require axial cable exit with mechanical strain relief. Typical use cases include:

• Aircraft and helicopter wiring harnesses with straight rear cable routing
• Ground vehicles and rugged electronic enclosures
• Avionics LRUs, radar, and communication equipment
• Shipboard and rugged industrial connector assemblies
• Cable-tension environments that need clamp-style strain relief without EMI braid termination

Selection Guide

Installation Notes

• Implement at least one anti-loosening method: safety wire through lock holes, thread-locking compound on the coupling nut, or full heat-shrink over the accessory.
• If clamp screws are used, apply thread-locking compound before final torque.
• Shell numbers for these accessories must be even; odd shell sizes are not used.
• For connectors with #8 contacts, consider longer cable accessories (e.g. M85049/49H or M85049/18A) to avoid interference with contact positioning hardware.
• Strain-relief-only backshells such as M85049/49-12W are best suited to clean, dry applications; for full environmental sealing plus EMI protection, select a shielded environmental backshell.

Why Choose M85049/49-12W

Form-Fit-Function Compatibility

Choosing the M85049/49-12W ensures form-fit-function compatibility with J1784/49-12W supply chains while meeting GJB1784 / AS85049 requirements. The straight HB clamp geometry secures axial cable exits behind Series I / II circular connectors, reduces strain on crimp terminations, and supports reliable operation in aerospace and industrial interconnect systems.

Ordering Information

Order by the AS85049 designation M85049/49-12W, or cross-reference as J1784/49-12W / industry code HB-B12, depending on your procurement standard.