1.The installing and mingling is easy, the efficacy and precision can be ensured. 2.The spindle the stroke have functions of changing speed in double frequencies braking and adjusting the rub patterns in mate easy. 3.The numeral showing operate screen in board can change the related parameter quickly. 4.Have functions of "designating", time and controlling.5.The double transmit tracks with high precision bearing in straight line sporting ,keep the reliability and stability. 6.Roundness : with 1um,size dispersion ratio: within 5um