The Stainless Steel Cold Trap simply slides into the silicone adapter, ensuring a snug fit. Using both products together will increase your efficiency, thanks to the lower vacuum depths you can achieve with fewer leak points in your system.
A silicone insulating ring also insulates the cold trap, which in turn helps keep the reservoir liquid (and the cold trap) as cold as the unit can be. This means that you’ll have a greater chance to catch volatiles that may have made their way past the initial system.