tires are exactly like sleeping bags ??? there are no true  four
season  tires,  as there are no four season sleeping bags... but for the
principle,   I can admit  that there are winter tires and there are winter
sleepings bags !!!   all depending where you live ... and  on the contrary,
you can find both
of these items  in a  three season  package , even if they are sold as all
seasons   ... I never sold tires,  but sleeping bags,   as a hobby. Snow
camping shoud be tried at least once in your life... nature is so different
surrounded by a all white winter coat !!!! light, no sounds etc etc... and
there are no heaters  used...because of a lot of  factors... except the one
you love... different kind of heat...

pierre a.