1- MAC 35A-AAA-DDBA-1BA Pneumatic Valve
1- 2 way connector kit (this make it plug and play for subaru applications)
The connector kit is fairly self explaining, you strip your wire, slip on the seal, then crimp on the pins and pull them through until they "click" into the connector. I also solder mine but that is optional although I would recommend it for a trouble free connection. These are not polarity specific it relies merely on a signal to actuate when needed so no need to fret over wire colors etc...
Optional which is how I mount them is to cut the old frame off of your stock BCS as shown in the photos below, and attach the new 3 Port Mac valve with the 3M tape. Keeping the rubber grommets helps to quite the clicking that you can hear if you mount it directly to the body.
You can also use whatever fittings you wish, the threads are 1/8 NPT, I've used these nylon ones for years and never had any issues with them. But use what you are comfortable with.
Have an EWG you can also use a 4 port version for better control, assembles just the same.