The MKS4O134706D00KSSD is a WIMA capacitor, specifically a 0.34 microfarad Polypropylene Monolithic KSSD Capacitor. This capacitor is rated for temperatures up to 125 degrees Celsius, and a voltage rating of 630 Volts DC. The KSSD capacitor is a surface mount capacitor, and it's very small in size making it ideal for use in circuit boards where space is at a premium. This capacitor is also considered to be self-healing and radiation-tolerant, and is widely used in industrial and military applications.