1.long using life 2.dust-proof & oil-proof 3.good cushion,shock absorption effect 4.CCC and CE certificate Roller lever type limit switch RL7121Operating characteristics Item CharacteristicsOF. max. 1.77N{180gf}RF. min0.49N{100gf}PT. max11mmMD. max2.4mmOT. min3.0mmOP40±1.99mmApplication: Food machinery, automatic packing machines,mahine tool, conveying machinery, auto production line control, ...