A clean example of Sinn's quietly remarkable flyback chronograph, recently discontinued. The 910 SRS sits in a rare category: a column-wheel-modified Valjoux 7750 with flyback function, finished and decorated, at a price point well below where column-wheel chronographs normally live. This reference recently went out of production, and most dealers no longer have stock. Production rarity: The serial number on this watch is in the high 500s. Sinn doesn't publish production figures for the 910 SRS, but given the model's price point, niche complication, and limited run before discontinuation, total production was almost certainly under 1,000 pieces. Sinn collectors will recognise what that means for future availability. Condition: Excellent throughout. Case unpolished and free of meaningful marks. Crystal clear. Dial and hands flawless. Recently timed on a timegrapher: 0 s/day, 0.2ms beat error, 334° amplitude — numbers consistent with a movement that's barely been run in. All functions working well. Provenance: Purchased 2 November 2024 from Sinn in Frankfurt. Full set: original Sinn box, papers, warranty card, instruction booklet, and outer carton. Factory warranty valid until 2 November 2026 — transferable with the original purchase documentation. Movement: Valjoux 7750 base, heavily modified by La Joux-Perret with column-wheel chronograph control and flyback function. 28,800 vph, 27 jewels, 48-hour power reserve. Decorated movement visible through sapphire caseback. Case: 41.5mm × 15.1mm stainless steel, polished and satinised finish. Sapphire crystal with AR coating front and back. D3 crown and pusher system. 100m water resistance. Strap: Original Sinn black leather strap with signed buckle.