The M85049/1921N05 is a straight, non-environmental EMI/RFI backshell featuring a spin coupling mechanism for easy installation onto MIL-DTL-38999 Series III & IV connectors. Constructed from aluminum alloy with a conductive, RoHS-compliant electroless nickel finish, it provides robust EMI/RFI shielding and strain relief. This backshell is specified for accessory shell size 21 and clamp size 05, accommodating a cable diameter range of 0.44 to 0.63 inches. Its operating temperature range of -65°C to +200°C makes it suitable for demanding applications where environmental sealing is not required, such as inside-the-box systems and climate-controlled environments.