Scale: 42 mm case Lug to lug estimated.
Swatch
Sistem51 Waktu51
SO30N400
about $196
Converted from the official €175 at 1 EUR = 1.121 USD on 9 October 2026.
Everyday, office
Sistem51 is still the cheapest Swiss automatic with a modern movement: 51 parts, one central screw, machine assembled, with a 90 hour power reserve and an antimagnetic hairspring. That reserve is more than double what most automatics give at twice the price. The Waktu51 is the plain navy version in a castor bean based case, with coloured dots on the dial that match the printed rotor seen through the back. It cannot be serviced, so buy it as an accurate, light automatic for daily wear.
A Swiss automatic with a 90 hour reserve for 175 euros.
Specifications
| Diameter | 42 mm |
|---|---|
| Thickness | 13.9 mm |
| Case | Bio sourced plastic |
| Water resistance | 30 m |
| Movement | Automatic |
| Calibre | Sistem51 |
| Power reserve | 90 hours |
| Strap | Bio sourced plastic strap |
Pros
- 90 hour power reserve
- Owners often report a few seconds a day
- Antimagnetic hairspring
- Movement on show through the back
Cons
- Sealed movement cannot be serviced or regulated
- Only 30 m water resistance, no date
- Online stock at Swatch is patchy
Rivals
Citizen C7 NH8390, Orient Bambino, Seiko 5 Sports SRPD
What owners say
WatchUSeek and WatchProSite owners mostly report accuracy within a few seconds a day, one measuring a steady 4 to 5 seconds fast over weeks, and they enjoy watching the rotor. The recurring complaints are that the movement is sealed, a minority of units drift out of spec or stop and need a warranty swap, and the light plastic case feels cheap next to steel.
Sources
- swatch.com Official · Current Swatch listing, EUR 175 incl. VAT
- swatch.com Official · Current Swatch Ireland listing, EUR 175
- swatch.com Official
- watchpapst.de Official
- zeitlounge.com Official
- ablogtowatch.com Review
- monochrome-watches.com Review
- europastar.com Review
- fifthwrist.com Review · Long term owner review: loud rotor, sealed movement
- watchprosite.com Forum · Owner measured +4 to +5 s per day over 2.5 weeks
- watchuseek.com Forum · Owner accuracy reports and long term reliability
- watchuseek.com Forum · Owner accuracy reports, some units out of spec
Some figures could not be verified: Price and current listing are official, but Swatch's product page publishes no specs and its online cart appears disabled; stock confirmed only at dealers. Case 42 x 13.9 mm and 3 bar are from dealers (some list 13.5 mm). Crystal is null because dealers disagree (plastic vs mineral). No date per Zeitlounge. Owner and review evidence covers the Sistem51 line, not this exact model. No Reddit thread reachable.