Safety-Certified SMD X1/Y2 & X2 250VAC Capacitors KEMET CAS Series Safety-Certified SMD X1/Y2 and X2 250VAC Capacitors are specifically designed for interference-suppression AC line filtering applications. When compared to radial leaded disc capacitors, the CAS surface-mount form factors provide engineers the ability to miniaturize their designs with a higher density solution. These capacitors offer internationally recognized safety certifications, making them well-suited for applications that require keeping potentially disruptive or damaging line transients and EMI out of susceptible equipment. They are also an ideal solution when line disturbances need to be suppressed at the source.