Now, the Sinn 155 is a great watch in it’s own right, but my brief period of ownership simply fuelled a desire to find the real thing, not for the first time. Sinn had produced a run of these watches as a consequence of having some left over cases from their contract with Heuer to refurbish the originals (and, subsequently, to produce their own Sinn-branded version). A little while ago, I bought Sinn’s reissue of the classic Heuer Bundeswehr 1550SG military chronograph, the 155.