This is a Bugcatcher - Birdcatcher hat line and feed line set. It also comes with a Kinsler square barrel valve.
This system came off a Bugcatcher that I bought. I have not done a leakdown test on the valve so I do not guarantee its condition. Hoses look great, but main feed line looks pretty old. Distribution block is real clean looking and has a custom mount attached to it that will bolt to the back of a standard sized 6-71/8-71 blower rear cover plate.