Greg, you are correct you only buy the shocks, they will send the springs.
Rule on the shock application is that if you weigh less than #230 pounds the suspension in a heavy duty would be too stiff. The 440 does not come in a Heavy Duty.
The total weight rule is If you and passenger are at or more than the recommended weight of the bike (Our bike is 460 pounds) or the rider is 230 plus a heavy duty shock in the lesser models 412 or 418 would be better suited.
I can't find the spot on the website where it was listed but I got it direct from Progressive.
