Part Number
Retaining Ring · OEM / vendor part number · NSN 5325-01-053-6183
| Part number | C9538-4 |
|---|---|
| Specification family | OEM / vendor part number |
| Item name | Retaining Ring |
| Alternate references | CA21037CL-4R; RR4040CL-4; 3D0164-4 |
| Unit of issue | EA |
| Cross-referenced NSN | 5325-01-053-6183 |
| Federal Supply Class (FSC) | 5325 — Fastening Devices |
| Unit price (USD) | $1.75 |
| Country of origin | Türkiye (Turkey) |
| Lead time | Within 90 days of order |
| Minimum order | May apply — confirm on quote |
| Documentation | Source documentation provided on all orders |
Characteristics decoded from the federal cataloging record for this retaining ring. Confirm controlling dimensions against your drawing or standard sheet before ordering.
| Material | Steel Comp 631 |
|---|---|
| Outside Diameter | 0.345 Inches Minimum And 0.355 Inches Maximum |
| Inside Diameter | 0.184 Inches Nominal |
| Surface Treatment | Cadmium And Chromate |
Quick-release and specialty fastening hardware including grommets, eyelets, snap fasteners, turnlock (Dzus/Camloc-type) fasteners, and retaining hardware.
Reading the part number. C9538-4 is a vendor part number for this retaining ring. If your documentation lists a different reference for the same item, include it on the quote and we will confirm the cross-reference.
Price in context. Across the 155 items we currently stock in FSC 5325 (Fastening Devices), published unit prices run from $0.18 to $1,752.30. At $1.75, this item sits well below the class median of $8.76 — commodity hardware usually bought in volume.
Stock activity. This item has appeared once in our supplier stock feed, most recently listed 2026-07-17, with a lot quantity of 54,452 units. Listing activity is a practical signal of ongoing availability; confirm current stock and firm pricing on your quote.
Who orders C9538-4. Aircraft owners and MRO shops replacing standard hardware, machine shops and OEMs filling a bill of materials, and government contractors sourcing against NSN 5325-01-053-6183. You can order by part number or by stock number — it is the same item, the same published price, and the same quote form.
Applicable standards. MS and NAS series turnlock and grommet standards.
Need this part modified, or a similar part made to your print? See our U.S.-based CNC machining services and aerospace machining capability.
Country of origin: Türkiye (Turkey). Turkey is a NATO ally and a normal-trade-relations partner of the United States, and Turkish-origin end items are eligible for a wide range of U.S. federal and DLA procurements.
TAA note: Turkey is not a Trade Agreements Act (TAA) designated country, so these items are generally not eligible for TAA-covered solicitations. They are offerable under the Buy American Act and many non-TAA DLA buys. Buyers are responsible for confirming the origin requirements of their specific solicitation.
Full country-of-origin and source documentation is provided with every order. Fulfillment within 90 days of order. Minimum order may apply.
Items are supplied as stock mil-spec / commercial hardware with source documentation and country-of-origin paperwork on every order. Parts are not supplied with an FAA Form 8130-3 airworthiness tag unless expressly stated on the quote. Buyers installing hardware on certificated aircraft are responsible for acceptance under their own maintenance program, repair station procedures, or owner/operator authority.
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