The CA-303 adaptor is a basic item to have in your "tricks and adaptors" kit. This is an all metal adaptor and is suitable for professional applications. There's nothing really special about this adaptor, it's just 3 pin Female XLR on both ends wired straight through:
Pin 1 to pin 1, pin 2 to pin 2, and pin 3 to pin 3.
This barrel adaptor is fully compatible with standard 3 pin XLR connections.
This is a professional grade adaptor, durably built with good quality contact springs in the Female connections. One set screw on each end holds the contact assemblies in the body.