Greetings Jim!
The 500 pound spring bars that I have are 2.5" shorter than
the 750 and 3.0" shorter than the 800 pound bars that I have
from the standard series. The 500 pound bars are also
signficantly lighter in their construction (cross-section is
noticeably thinner). In my case, the 750 and 800 pound bars
are easy to distinguis as the 750 pound bars are of the
older design that require the special saddles for the Dual
Cam Sway control while the 800 pound bars are of the new
design with the down-turned ends that do not require special
saddles for use with the Reese Dual Cam Sway control.
If you need even lighter weight distributing bars, there is
(or at least was) a 350 pound bar set available in the
ligth-weight series when I purchased mine several year ago.
Kevin D. Allen
WBCCI/VAC #6359
1964 Overlander International/1999 GMC K2500 Suburban
1978 Argosy Minuet 6.0 Metre/1975 Cadillac Eldorado
Convertible