I made mine out of an old A/C receiver dryer. I gutted the insides, made a hole in the end for the filter and used PVC connectors. I had the guy at the parts store look around for curved hoses till we found one that would work. The engine vents to the oil tank then this vents the oil tank. The small line is there simply because I didn't have a fitting to plug the hole so I just put a line on it and and it also goes to the oil tank PCV connection. I got the reciever for free from the scrap pile at a radiator shop.
Forgot to mention if you do this put the hole for the filter in the other end.
