NAICS Code

333613

Mechanical Power Transmission Equipment Manufacturing

NAICS 333613 obligated $367 million in FY2025 and 98.7 percent of it was DoD. Bearings, couplings, and drive components for shipboard and ground equipment.

SBA size standard

750 employees

Measured by average number of employees over the last 24 months

SBA table effective March 2023

By Outrider Editorial Team · Updated August 20, 2026

Official definition

This U.S. industry comprises establishments primarily engaged in manufacturing mechanical power transmission equipment (except motor vehicle and aircraft), such as plain bearings, clutches (except motor vehicle and electromagnetic industrial control), couplings, joints, and drive chains.
U.S. Census Bureau, NAICS 2022

FY2025 obligations

$367.1M

Contract actions

7,078

IDVs

553

Top buying agencies

  1. Department of Defense$362.0M
  2. Department of Homeland Security$5.0M
  3. Department of the Interior$49.0K
  4. Department of Health and Human Services$37.6K
  5. Department of Veterans Affairs$36.5K

FY2025 federal contract obligations, USAspending.gov

NAICS 333613 obligated $367 million in FY2025 across 7,078 contract actions. DoD is $362 million, or 98.7 percent, with DHS at $5 million and nothing else measurable. At an average near $52,000 per action, this is component sustainment for machinery already in service, concentrated in shipboard auxiliary systems, ground vehicle drivetrains, and depot equipment.

What belongs here

Mechanical power transmission equipment other than motor vehicle and aircraft: plain bearings, clutches other than motor vehicle and electromagnetic industrial control, couplings, joints, and drive chains.

  • Motor vehicle transmissions and power train parts are 336350.
  • Non-aircraft, non-automotive engines are 333618.
  • Valves in the same fluid and mechanical systems are 332911.

Competing in this code

553 IDVs against 7,078 actions puts most volume behind long-term supply contracts. The technical gate that matters is material and process certification: shipboard drive components frequently carry specification requirements on material composition, heat treatment, and nondestructive inspection that commercial bearing and coupling suppliers do not routinely document. A supplier that builds the certification package once, for a family of part numbers, converts a low-margin commodity into repeat qualified-source business. The 750-employee size standard keeps that supplier small by federal definition for a long time.

Frequently Asked

NAICS 333613 questions, answered.

What is the SBA size standard for NAICS 333613?

SBA sets it at 750 employees, counted as a 24-month average headcount across your company and every affiliate, not revenue. At or under that number you are small on NAICS 333613 solicitations and eligible for the set-asides in this code.

Which agencies buy power transmission components under NAICS 333613?

FY2025 obligations: DoD ($362 million), DHS ($5 million). At 98.7 percent DoD this is effectively a defense sustainment code, concentrated in shipboard auxiliary systems and ground vehicle drivetrains.

What separates NAICS 333613 from 336350?

Application. 333613 covers mechanical power transmission equipment excluding motor vehicle and aircraft uses: plain bearings, couplings, joints, drive chains, and non-vehicle clutches. 336350 is specifically motor vehicle transmissions and power train parts. A supplier serving both markets needs both registrations, because the buying communities do not overlap.

What certification do federal drive component buys require?

Frequently material composition, heat treatment, and nondestructive inspection documentation tied to a military or federal specification, particularly for shipboard applications. Commercial bearing and coupling suppliers usually have the capability but not the documentation package, and building it once for a part family creates a durable qualified-source position.

Register Under NAICS 333613

Classify your business correctly to maximize visibility to federal buyers and access small business set-asides.

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