There are none. Subsequent generations have differing ports, so chassis has to change as well. Besides, the BN NUCs are from the Enthusiast category and Intel only sells bare boards in the Pro category.
P.S. You can let go of the Shift key any time now.
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Due to this product being discontinued, Intel Customer Service no longer supports inquiries for it, I am glad to see that fellow community members have the knowledge, and they jumped in and helped. You may also find the Discontinued Products website (https://www.intel.com/content/www/us/en/support/discontinued-products.html) helpful to address your request. You can get the specifications and verify this product's discontinuance status at the Intel® Product Specifications website > Product Status > "Discontinued". https://ark.intel.com/
Discontinued Intel Products – Customer Support Options, provides a list of discontinued products by product family.
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