PartsTable TECHNICAL DATA SHEET
JULY 2026Technical Data Sheet

12521Cap,filler Opening

Generac Mobile Products, Llc · NSN 5340-01-537-9974 · FSC 5340 · No Item Name Available
Verified by PartsTable
NSN 5340-01-537-9974 — this item is cataloged by the U.S. Government under National Stock Number 5340-01-537-9974. Primary manufacturer part number: 12521.
Features
  • Cap,filler Opening — FSC 5340
  • 2 verified cross-references
  • Primary manufacturer: Generac Mobile Products, Llc
Applications
  • General assembly and fastening
  • Structural repair and reinforcement
  • Facility maintenance hardware
General Description

The Cap,filler Opening, cataloged under National Stock Number 5340-01-537-9974, is classified within Federal Supply Class 5340 (No Item Name Available) of the Hardware and Abrasives group. The primary manufacturer of record is Generac Mobile Products, Llc. This item has 2 commercial cross-references from 2 manufacturers, enabling identification through both NSN and commercial part number lookups. 10 verified substitutes exist in the FLIS interchangeability database. Current acquisition status: Active. Unit of issue: EA.

Technical Specifications
ParameterValue
NSN5340-01-537-9974
Primary Part Number12521
Item NameCap,filler Opening
FSC / FSG5340 / 53 — No Item Name Available
ManufacturerGenerac Mobile Products, Llc
StatusACTIVE
Lifecycle & Compliance
Acquisition StatusACTIVE
HAZMATNo
Unit of IssueEA
Verified Substitutes 10
5340-00-721-7226930-3 SUCCESSOR
Handle,bow
Goe Engineering Co Inc
5133-00-227-5966 INTERCHANGEABLE
Drill,twist
5315-00-282-687912521 INTERCHANGEABLE
Pin,straight,headless
Rtx Corporation Dba Pratt & Whitney Div Pratt &whitney
4730-00-289-5268 INTERCHANGEABLE
Packing Nut
5935-00-430-6877ST5M1348TS1C INTERCHANGEABLE
Connector,plug,electrical
The Boeing Company Div Defense
5930-00-655-1513 INTERCHANGEABLE
Switch,toggle
5930-00-883-01282615080-016 INTERCHANGEABLE
Switch,push
Navair and Navsea Managed Original Design Activity Dwg Not Material/parts Supplier
5950-00-954-4496900123-35 INTERCHANGEABLE
Transformer,power
Northrop Grumman Systems Corporation Dba Northrop Grumman Systems Corp
4820-01-303-1107 INTERCHANGEABLE
Valve,gate
3020-01-628-502812521 INTERCHANGEABLE
Rod,pinion
Barrett Firearms Manufacturing, Inc. Dba Barrett Firearms Manufacturing Inc
Cross-Reference Index
Part NumberManufacturer
12521 Kelch Corp (USA)
12521 PRIMARY Generac Mobile Products, Llc (USA)
Related Parts
5340-00-721-7226SUCCESSOR
HANDLE,BOW
930-3
5133-00-227-5966INTERCHANGEABLE
DRILL,TWIST
5315-00-282-6879INTERCHANGEABLE
PIN,STRAIGHT,HEADLESS
12521
4730-00-289-5268INTERCHANGEABLE
PACKING NUT
5935-00-430-6877INTERCHANGEABLE
CONNECTOR,PLUG,ELECTRICAL
ST5M1348TS1C
5930-00-655-1513INTERCHANGEABLE
SWITCH,TOGGLE
5930-00-883-0128INTERCHANGEABLE
SWITCH,PUSH
2615080-016
5950-00-954-4496INTERCHANGEABLE
TRANSFORMER,POWER
900123-35
4820-01-303-1107INTERCHANGEABLE
VALVE,GATE
3020-01-628-5028INTERCHANGEABLE
ROD,PINION
12521

Frequently Asked Questions

What is NSN 5340-01-537-9974?

NSN 5340-01-537-9974 is a Cap,filler Opening, manufactured by Generac Mobile Products, Llc, classified under FSC 5340 (No Item Name Available). Status: active.

What are the part numbers for NSN 5340-01-537-9974?

NSN 5340-01-537-9974 has 2 cross-referenced part numbers: 12521 (Kelch Corp), 12521 (Generac Mobile Products, Llc).

What NSN replaces 5340-01-537-9974?

There are 10 known substitutes for 5340-01-537-9974: 5340-00-721-7226, 5133-00-227-5966, 5315-00-282-6879 and 7 more. Verify interchangeability with system specifications before substitution.

What are the specifications of 12521?

Key specifications for 12521: Part Name Assigned by Controlling Agency: CAP, FUEL TANK BLK; End Item Identification: 6230-01-530-8890. 2 total characteristics are documented in the Federal Logistics Information System.

Validated with multiple authoritative sources, including Government, OEM, and Certified sources.
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