This SH4131 was built based on SH4130 and has 75h power reserve. Clean took part in the movement building with SH(Jinghe) movement factory and in charge of the movement polishing, plating, engraving and assembling. This means Clean has the exclusivity to SH4131 movement.
Clean has done a lot of improvements on SH4131, such as overall polishing, reshaping oscillating rotor, upgrading the rotor bearing, rebuilding the auto device bridge, changed the shock absorbing part of the balance wheel... The problems like chronograph hand wrongly zeroing on SH4130 will be solved this time. The stability of this movement is much better after testing.