Sinn has made multiple successors to the 1550 sg produced by Heuer and Sinn. The Sinn 1550sg was directly succeeded by Sinn 156 and Sinn 156b and then followed by Sinn 155 and Sinn 158. Whereas the Sinn 155 is more true to the 1550 sg, the Sinn 158 sits somewhere between 1550 sg and 156b.
The elephant in the room is that neither Sinn 158 or Sinn 155 Darkstar was sold on steel bracelet whereas with Sinn 156 the bracelet was always an option. This leaves many Darkstar and Sinn 158 owners yearning for that cold hard steel on their wrists. The situation is bad, but it is not intolerable. Before the Darkstar and the Sinn 158, Sinn produced various watches with the reference Sinn 155. One of the came with steel bracelet.
First of the series is Sinn 155 ‘Manufactum’ with Valjoux 7750 movement. This was limited edition of 272 to the German market, sold via Manufactum. This watch features day/date chronograph seconds, minute register at top and hour register in bottom. I haven’t personally handled this watch, so I don’t know what the case is like. However, judging from pictures this is where the series begins.
The second entry to the series is Sinn 155 ‘Replica’, again a 300 piece limited edition made only for the Japanese market. The bracelet was optional for these watches. This watch features classic two register layout with minutes on the right and seconds on the left. Unlike the other versions, this watch uses manual wind movement. Judging from the packaging of the bracelet, the bracelet was supplied separately.
Finally, the third iteration before 158 is the Sinn 155 Darkstar collaboration with The Rake and Revolution magazine. Owners of these watches are in similar position as owners of Sinn 158. The Darkstar is very similar to the Sinn 155 ‘Replica’, but has automatic SW510 movement. Additionally, the Darkstar features a black star on the dial and faux lume, which makes it very attractive to those who want a modern equivalent to the Sinn 1550sg.
The cases of Sinn 155/158 and Sinn 156b are not identical, so it is unlikely that the SEL bracelet of Sinn 156b will fit. The hollow end-link bracelet might, but until I have access to one, this remains to be a mystery. The solution for owners of the Sinn 155 Darkstar and the Sinn 158 is to acquire a bracelet for the Sinn 155 Replica. The cases of all these models seem to be identical.
In conclusion, the solution is not without problems. These bracelets are rarer than either Sinn 155 Darkstar or Sinn 158. However, they are a perfect fit. Those bothered by the Sinn 155 text on the bracelet can swap any bead-blasted Sinn clasp and have their nightly sleep. The end result is great and completes the watch.