The Back-Up Ring,preformed Packing, cataloged under National Stock Number 5330-01-553-4644, is classified within Federal Supply Class 5330 (Packing and Gasket Materials) of the Hardware and Abrasives group. The manufacturer of record is Naval Inventory Control Point Mechanicsburg. Government technical data includes 7 specifications, cited from the U.S. Government catalog. The record lists 3 manufacturer part numbers for this item, enabling identification through both NSN and commercial part number lookups. 4 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5330-01-553-4644 |
| Primary Part Number | MS28774-431CP |
| Item Name | Back-Up Ring,preformed Packing |
| FSC / FSG | 5330 / 53 — Packing and Gasket Materials |
| Manufacturer | Naval Inventory Control Point Mechanicsburg |
| Status | ACTIVE |
| Cross-Sectional Height | 0.110 INCHES NOMINAL IN |
| Criticality Code Justification | ZZZW |
| Cross-Sectional Shape Style | SINGLE TURN SPIRAL |
| Departure From Cited Document | CLEANING, PACKAGING, AND MARKING IAW MIL-STD-1330D |
| Peripheral Diameter | 5.773 INCHES NOMINAL IN |
| Center Hole Diameter | 5.301 INCHES NOMINAL IN |
| Material | PLASTIC |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | Possible hazard — SDS may be required (DLA HMIC P) |
| Criticality Code | S |
| Part Number | Manufacturer |
|---|---|
| MS28774-431CP | Naval Inventory Control Point Mechanicsburg (USA) |
| 803-INC6701-A ITEM NO.21CP | Naval Inventory Control Point Mechanicsburg (USA) |
| 54-94-7431MRCP | Naval Inventory Control Point Mechanicsburg (USA) |
| Reference | Meaning |
|---|---|
| 54-94-7431MR | 5/1 Secondary reference U.S. Government activity |
| MS28774-431 | 5/1 Secondary reference U.S. Government activity |
| CD-023-42-21CP | 3/1 Design control — primary reference Naval Inventory Control Point Mechanicsburg |
| 803-INC6701-A ITEM NO.12 | 5/1 Secondary reference Naval Sea Systems Command |
NSN 5330-01-553-4644 is a Back-Up Ring,preformed Packing, manufactured by Naval Inventory Control Point Mechanicsburg, classified under FSC 5330, Packing and Gasket Materials. Status: active.
NSN 5330-01-553-4644 has 3 manufacturer part numbers on file: MS28774-431CP (Naval Inventory Control Point Mechanicsburg), 803-INC6701-A ITEM NO.21CP (Naval Inventory Control Point Mechanicsburg), 54-94-7431MRCP (Naval Inventory Control Point Mechanicsburg).
Key specifications for MS28774-431CP: Cross-Sectional Height: 0.110 INCHES NOMINAL IN; Criticality Code Justification: ZZZW; Cross-Sectional Shape Style: SINGLE TURN SPIRAL; Departure From Cited Document: CLEANING, PACKAGING, AND MARKING IAW MIL-STD-1330D. 7 specifications are documented in the U.S. Government catalog.
Possible hazard — SDS may be required (DLA HMIC P). Hazard information on this page is shown exactly as it appears in the DLA record.
U.S. Government catalog: edition PUBLOGDVD v12.0.0 (OCT 2026), edition date 2026-10-01, retrieved 2026-10-16.
U.S. Government catalog: edition PUBLOGDVD v12.0.0 (OCT 2026), edition date 2026-10-01, retrieved 2026-10-18.