Alternative Replacement for HEC HT50 HT57 & Vishay RF Power Barrel Capacitors HEC's HT50 HT57 series and Vishay TOS 030033 and TOS 020016 Series are major RF power barrel capacitors producers in the world. https://www.hv-caps.com/products/H-F-RF-Power-Capacitor/2021/1029/48927.html RF power barrel capacitors,HEC HT50, HEC HT57