Schwalbe always provides complete information about inner tube compatibility on the packaging of their products. It is what they do. I worked for a company that distributed Schwalbe products. The ISO measurements are always the most reliable, but inner tubes have a huge fudge factor. As an aside, most tire measurements that are in inches have nothing to do with the actual size of the wheel rim. Rather, they relate to the outside diameter of the inflated tire. So, the 28" nominal tire size on the inner tube box is only for narrow road tires, but the same rim size is also designated as 29" with wider mountain bike tires. Sounds confusing except that it isn't a big deal. For someone using 700 x 32 tires, an inner tube that claims to work for 700 x 28 tires will probably be just fine, the inner tube is just a baloon that will fill up the inside of your tire and cause no problems