Yes, this little thing really will fix your flat.  Even huge pick-up and SUV tires.  No need to jack up.  Just press the nozzle and it repairs and re-inflates your tire.  You definitely should carry one in your car or truck.

This amazing can of stuff will also PREVENT flats and slow leaks.  Fix-A-Flat inserts a complex liquid into your tire.  Leaking air instantly polymerizes it to plug up any hole.  This magic material is similar to the stuff which keeps bicycle tires intact.  The Army uses a similar compound to keep their tires going