All of the traits described are common to the entire MBII and, by extension, U-2 watch family. So the rather oddly-named U-2/51-Jet then, is really more of a design derivation of an existing watch, but despite its similarities, it is a significant change. First off, the “51-Jet” name gives some clues. The “Jet” refers to the black case and barrel finishing, which was derived from a military edition made at the request of the RAF’s 100 Squadron. “51” refers to the P-51 Limited Edition Bremont made several years ago that made use of a tinted luminescent paint that falls somewhere between ecru and café au lait. The color was popular enough that Bremont has since used it again on a version of its ALT1-ZT chronograph. Set off against the black case and minimalist dial of the U-2, it adds a warmth to what could otherwise be a very stark watch.