1、High rated switch voltage reaches 440V and insulation voltage reaches AC 660V. 2、There are 4 kinds of button switch of different colors for you to choose from. 3、The contact material is silver alloy of low resistance and high conduction. 4、Long service life.The mechanical service life reaches 5000000 times and electronic service life reaches 500000 times. 5、This button is suitable for action control in AC 50Hz, voltage 380V and below, DC and below electromagnetic starters, contactors, relays and other electrical circuits. Features: There are 4 kinds of button switch of different colors for you to choose from. The contact material is silver alloy of low resistance and high conduction. Long service life.The mechanical service life reaches 5000000 times and electronic service life reaches 500000 times. Specification: Model:BEM38-11S Ui:AC660V Working Current:10A Function:Self-Locking Contact Mode:1 on 1 off Installation Hole Diameter: 22mm/0.87in Rated Heat Current: 15A Contact Material:Silver alloy Contact Resistance: 50ohm Insulation Resistance: 50Mohm Mechanical Life:5000000 times Electronic Life:500000 times Size:66 x 35 x 29mm / 2.6 x 1.38 x 1.14in Package List: 10 x Button Switch