What This Backshell Does That a Bare D-Sub Connector Can't
The TE Connectivity 5748676-1 is a two-piece metal backshell from the AMPLIMITE HD-20 series, designed to fit standard 9-position D-sub connectors and high-density 15-position connectors sharing shell size E. Its primary job is to shield the cable-to-connector junction and provide strain relief, which a bare D-sub connector alone cannot do. The 180° cable exit keeps the cable running straight out the back, which is the standard orientation for panel-mount applications where the connector passes through a cutout and the cable routes into an enclosure.
What's in the Bag: Hardware and Assembly Details
This backshell ships in bulk and includes the assembly hardware and grommets needed for a complete cable termination. The 4-40 mating screws are the standard thread for D-sub jack-screw retention, so you don't need to order them separately. The grommets provide strain relief at the cable entry point, gripping the round cable jacket to prevent pull-out forces from reaching the solder or crimp terminations inside the D-sub connector. The two-piece design means you can install the backshell after the cable is terminated, which is the typical assembly sequence for field-terminated or low-volume harness builds.
Shielding Performance and Cable Fit
The shielded construction is the main reason to choose this backshell over a plastic or non-metallic alternative. The nickel over copper plating on the zinc alloy body provides a low-resistance path to ground when the backshell is clamped over the cable braid and mated to the D-sub connector's metal shell. This is critical for applications where the cable run passes through electrically noisy environments, such as industrial control cabinets or near motor drives. The backshell accepts round cable only; it is not designed for flat ribbon cable or FFC. The 180° cable exit means the cable exits straight out the back, which is the most common orientation for panel-mount D-subs where the connector is mounted to a bulkhead or enclosure wall.