# Mechanical differences between BB-UD1-B-1, BB-UD1-C-1 and BB-UD1-B-1-NDAA

**URL:** <https://forum.botblox.org/t/mechanical-differences-between-bb-ud1-b-1-bb-ud1-c-1-and-bb-ud1-b-1-ndaa/505>\
**Category:** BotBlox Hardware\
**Tags:** ubiswitch\
**Created:** [October 29, 2025, 6:57pm UTC](https://forum.botblox.org/t/mechanical-differences-between-bb-ud1-b-1-bb-ud1-c-1-and-bb-ud1-b-1-ndaa/505 "2025-10-29T18:57:55Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![Tpow](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.botblox.org/tpow/32/514_2.png) [@Tpow](https://forum.botblox.org/u/Tpow)\
**Post date:** [October 29, 2025, 6:57pm UTC](https://forum.botblox.org/t/mechanical-differences-between-bb-ud1-b-1-bb-ud1-c-1-and-bb-ud1-b-1-ndaa/505/1 "2025-10-29T18:57:55Z")

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It seems like there is no mechanical differences between these three part numbers because there is only CAD for PN: BB-UD1-B-1. Can you confirm that there is no mechanical differences between these different versions/revisions that could cause interference if I am using the only CAD model provided (BB-UD1-B-1). Is there going to be a revision C of the NDAA compliant board?

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**Author:** ![josh\_elijah](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.botblox.org/josh_elijah/32/568_2.png) [@josh\_elijah](https://forum.botblox.org/u/josh_elijah)\
**Post date:** [October 29, 2025, 8:00pm UTC](https://forum.botblox.org/t/mechanical-differences-between-bb-ud1-b-1-bb-ud1-c-1-and-bb-ud1-b-1-ndaa/505/2 "2025-10-29T20:00:44Z")

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Thanks for posting. That’s right, there is no mechanical difference between the two models.

There will likely be a revision C of the NDAA compliant version in the future, probably in a few months or so.

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**Author:** ![Tpow](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.botblox.org/tpow/32/514_2.png) [@Tpow](https://forum.botblox.org/u/Tpow)\
**Post date:** [October 29, 2025, 11:33pm UTC](https://forum.botblox.org/t/mechanical-differences-between-bb-ud1-b-1-bb-ud1-c-1-and-bb-ud1-b-1-ndaa/505/3 "2025-10-29T23:33:33Z")

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Thank you. Is there any BOM differences or any other differences between BB-UD1-B-1 and BB-UD1-B-1-NDAA. We just need to confirm that the radiation testing is applicable to both versions. Same question for BB-UBS-B-1 and its NDAA version.