SELLITA WATCH MOVEMENTS
It was reported in the AWCI that "Several independent Swiss watch manufacturers are now using mechanical movements made by the Sellita Watch Company of Switzerland. Watchmakers viewing these movements for the first time can easily mistake them for ETA products, as they appear to be exactly like the more familiar ETA movements. However, do not be fooled, they are NOT ETA movements.
They are marked SW200, SW200-1, SW220-1, SW240-1, SW260-1, SW300, or SW500. The ETA trademark does not appear anywhere on these movements. The movements in the SW2XX series are very similar to the ETA 2824, 2834, 2836 series. The SW300 movements bear a close resemblance to the ETA 2890-based movements while the SW500 series is strikingly similar to the ETA 7750 series of movements.
Anyone familiar with the ETA analogs of these Sellita movements should have no difficulty servicing Sellita products. Some, but not all ETA movement parts are interchangeable with their analogous Sellita movements. Many, but not all, ETA parts will properly fit Sellita movements. You will need to order genuine Sellita parts when an ETA part cannot be substituted. You will definitely be seeing these movements in for service. Last year, Sellita produced its millionth movement, making it apparent that they are not just a limited focus, niche movement manufacturer".
quoted from Cousins UK