Thanks to my knowledge gained in practice I can SAY that this Tech Extension Connector Disconnect is a valuable addition to any automotive toolbox. It makes disconnecting batteries and jump starter connections easy, quick and safe. The compact size of the connector also makes it easy to store or carry in a toolbox or glove compartment .The only con was that it took me a little while to figure out how to use it properly, but once I did, it was smooth sailing. Overall, I highly recommend this product to anyone looking for an easy disconnect solution..