QMPC-100 is an all-fiber manual polarization controller. It is well designed for applications which require polarization controlling and compensation, and suitable for optical device test and manufacture. The three adjusting circles are equivalent in function to quarter-wave plate, half-wave plate and quarter-wave plate respectively, which can manipulate the state of polarization (SOP) efficiently to any desired position on the Poincare sphere. The features of QMPC-100 include entire-fiber construction, low insertion loss, large operating range, high returnloss, lowcost, low weight, portable and easily operating. It is a cost-effective polarization controlling product in the fiber optical communication domain.