PartsTable TECHNICAL DATA SHEET
JULY 2026Technical Data Sheet

B21-24Gear,spur

Designatronics Incorporated Div Sterling Instruments Div · NSN 3020-00-229-6942 · FSC 3020 · No Item Name Available
Verified by PartsTable
NSN 3020-00-229-6942 — this item is cataloged by the U.S. Government under National Stock Number 3020-00-229-6942. Primary manufacturer part number: B21-24.
Features
  • Gear,spur — FSC 3020
  • Body Style: PLAIN, SOLID
  • Material Document and Classification: MIL-S-7720 MIL SPEC SINGLE MATERIAL RESPONSE OVERALL
  • Teeth Quantity: 24
  • Bore Style: PLAIN BOTH ENDS
  • Style Designator: PROTRUDING HUB
  • Backlash Designation: GRADE C
  • Surface Treatment: PASSIVATE OVERALL
Applications
  • Power transmission and speed reduction
  • Rotary motion transfer
  • Torque multiplication
  • Applications requiring Steel Comp 303s or Steel Comp 303SE Overall construction
General Description

The Gear,spur, cataloged under National Stock Number 3020-00-229-6942, is classified within Federal Supply Class 3020 (No Item Name Available) of the Mechanical Power Transmission Equipment group. The primary manufacturer of record is Designatronics Incorporated Div Sterling Instruments Div. Government technical data includes 19 verified specifications, sourced from the Federal Logistics Information System (FLIS). This item has 5 commercial cross-references from 5 manufacturers, enabling identification through both NSN and commercial part number lookups. 4 verified substitutes exist in the FLIS interchangeability database. Current acquisition status: Active.

Technical Specifications
ParameterValue
NSN3020-00-229-6942
Primary Part NumberB21-24
Item NameGear,spur
FSC / FSG3020 / 30 — No Item Name Available
ManufacturerDesignatronics Incorporated Div Sterling Instruments Div
StatusACTIVE
Body StylePLAIN, SOLID
Material Document and ClassificationMIL-S-7720 MIL SPEC SINGLE MATERIAL RESPONSE OVERALL
Teeth Quantity24
Bore StylePLAIN BOTH ENDS
Style DesignatorPROTRUDING HUB
Backlash DesignationGRADE C
Surface TreatmentPASSIVATE OVERALL
Nominal Overall Length0.312 INCHES IN
Hub Nominal Diameter0.312 INCHES FIRST END IN
Precision ClassificationQUALITY NUMBER 10
Nominal Outside Diameter0.541 INCHES IN
Pressure Angle20.0000 DEGREES
Tooth FormSTANDARD
Face Nominal Width0.125 INCHES IN
Pitch Diameter0.4990 INCHES MINIMUM AND 0.5000 INCHES MAXIMUM IN
Hub Style DesignatorPINNED FIRST END
MaterialSTEEL COMP 303S OR STEEL COMP 303SE OVERALL
Bore Nominal Diameter0.125 INCHES BOTH ENDS IN
Nominal Distance Between Body Face and Protruding Hub End0.187 INCHES FIRST END IN
Lifecycle & Compliance
Acquisition StatusACTIVE
HAZMATNo
Verified Substitutes 4
3110-00-902-1641B-2 1/2 4 INTERCHANGEABLE
Bearing,roller,needle
Jtekt Bearings North America Llc Div Kbna - Ord 1
3110-00-935-5613125-3818 INTERCHANGEABLE
Bearing,roller,needle
Drs Naval Power Systems Inc Dba Drs Power & Control Technologies Inc
3110-01-273-99104032157-0702 INTERCHANGEABLE
Bearing,roller,needle
Raytheon Company Dba Raytheon Co
3455-01-274-3720CNMG-431/K68 INTERCHANGEABLE
Insert,cutting Tool
Kennametal Inc. Div Charlotte Business Office
Cross-Reference Index
Part NumberManufacturer
B21-24 PRIMARY Designatronics Incorporated Div Sterling Instruments Div (USA)
75-805390-1 General Dynamics Advanced Information Systems Inc. Dba General Dynamics Advanced Information Systems (USA)
GP18-24P1 PRIMARY Secs Inc (USA)
A200-24P1 Continental Gear Co (USA)
10669698-1 Us Army Aviation and Missile Command (USA)
Related Parts
3110-00-902-1641INTERCHANGEABLE
BEARING,ROLLER,NEEDLE
B-2 1/2 4
3110-00-935-5613INTERCHANGEABLE
BEARING,ROLLER,NEEDLE
125-3818
3110-01-273-9910INTERCHANGEABLE
BEARING,ROLLER,NEEDLE
4032157-0702
3455-01-274-3720INTERCHANGEABLE
INSERT,CUTTING TOOL
CNMG-431/K68

Frequently Asked Questions

What is NSN 3020-00-229-6942?

NSN 3020-00-229-6942 is a Gear,spur, manufactured by Designatronics Incorporated Div Sterling Instruments Div, classified under FSC 3020 (No Item Name Available). Status: active.

What are the part numbers for NSN 3020-00-229-6942?

NSN 3020-00-229-6942 has 5 cross-referenced part numbers: B21-24 (Designatronics Incorporated Div Sterling Instruments Div), 75-805390-1 (General Dynamics Advanced Information Systems Inc. Dba General Dynamics Advanced Information Systems), GP18-24P1 (Secs Inc), A200-24P1 (Continental Gear Co), 10669698-1 (Us Army Aviation and Missile Command).

What NSN replaces 3020-00-229-6942?

There are 4 known substitutes for 3020-00-229-6942: 3110-00-902-1641, 3110-00-935-5613, 3110-01-273-9910 and 1 more. Verify interchangeability with system specifications before substitution.

What are the specifications of B21-24?

Key specifications for B21-24: Body Style: PLAIN, SOLID; Material Document and Classification: MIL-S-7720 MIL SPEC SINGLE MATERIAL RESPONSE OVERALL; Teeth Quantity: 24; Bore Style: PLAIN BOTH ENDS. 20 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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