开式托辊轴承常用型号: 6204 6205 6206 6305 6306 6307 6308 6204/C3 6205/C3 6206/C3 6305/C3 6306/C3 6307/C3 6308/C3 6204/C4 6205/C4 6206/C4 6305/C4 6306/C4 6307/C4 6308/C4