The 26 is 26 threads per inch, commonly used by Campagnolo or Joytech. Another common size is 10x1, which is Shimano and several french hubs
Your hub could be either, there are many mfgrs.Your 146, is the total axle length, assuming it's a QR. The 135 is the outer locknut distance. (outside to outside). You have a freewheel type system, because the axle is supported up under the freewheel, it is prone to bending/ breaking. The freehub system gives better axle support, and riders tend to have a lot less problems with bending/ breaking axles. Wheel master is just the wheel builder, not a component, per say.