The Rigidaire system comes complete with everything you'll need to make your hardtail more comfortable, including: a steel air spring frame bracket, two air springs, top plate, seat adapter, mounting hardware, solenoid air valve, air lines and fittings, air compressor and bracket, toggle switch, in-line fuse, seat nose mount assembly, 14-gauge wire, and a razor for cutting the air lines. Note the air spring system assembly as it is packaged. You will need to disassemble the parts to install it.
Anyone who's ever spent any time on a rigid knows that sometimes the going gets a little rough. Whether it's the general condition of the bumpy roads in California or the manhole-cover-sized potholes in New York City, riding a rigid can be a pain in the ass. Thankfully, there are innovative guys in the industry, like Paul Cox, who want to make riding a rigid more comfortable and a little easier on the 'ol rear end. Cox created the Rigidaire seat suspension system that incorporates a pair of airbags to cushion your body from all the cruel bumps in the road. His system works without catapulting you out of your seat when you hit something on the street, like standard springs or just a seat pad. Plus, the onboard compressor allows the rider to adjust for seat height and the amount of shock-absorption while riding.
We just happened to be in Brooklyn, New York, for a little while, so we stopped by Paul's shop and got a few pics of him installing the system.
Cox started by using a sawzall to remove the rear crossmember from the frame. | 
Once the crossmember was removed, he ground the frame tubes down until he had a smooth, clean surface to weld the air spring bracket to. | 
The air spring bracket is designed to fit a variety of frames. In most cases, a small amount of material will need to be removed from either side of the bracket. With the bracket held in place and centered in the frame, mark the bracket where the extra material needs to be removed. |
Taking caution to remove a little bit from the bracket at a time, Paul Cox cut and tested the fit a few times. | 
He then used a belt sander to clean up the burrs from the cutting saw. | 
When properly aligned, the bracket should measure about 3 inches from the top of the frame tubes. |
(From the "Do as we say, not as we do" department) Paul is a badass and you're not, so use gloves and clamps when tacking the bracket in place. | 
Double-check to make sure the system is level with the framerails by mocking up the air springs and measuring again before making the final welds. | 
When the bracket is installed correctly, there should still be plenty of room behind the seat tube for an oilbag and battery box. |