The Marathon Plus is the only true flat-less tyre. The patented, 5 mm thick SmartGuard layer, when compared to all generic products has a significant advantage in rolling resistance.
PSI by size:
700 x 28 - 55 to 100
700 x 32 - 55 to 95
26" x 1.5 - 50 to 85
In the SmartGuard, a proportion of recycled rubber from old latex products is used.
With "anti-aging" side walls, it now lasts much longer before developing unsightly cracks when subjected to use with too low air pressure.