THE CIMPLE CO, A Family Company located in the USA, is proud to offer these high quality and durable VBTs, also known as Voltage Blocking Terminators. F81 Terminators, using the F-Pin connection (standard on US Cable systems). These connectors may be installed indoors or outdoors - ensuring that the female port stays clean and free from dust, dirt, rust, or debris. They also block the DC Voltage on signal lines. Standard 75 Ohm Terminators do not block voltage, only this style does. We back our product 100%.