Wheel choice:
While choosing a wheel, you'd consider several elements: what size and load, pneumatic or solid, or semi-pneumatic, steel or plastic rim, hub length, bearing diameter etc.

Commonly: a wheel includes:

Tires: different tire thread, 2PR or 4PR
Tubes: natural or butyl tube
Rim: Steel or plastic rim, offset or centered. If steel, powdered coated, or zinc plated.
Bearing: ball bearing, roller bearing or nylon/steel bushing
Details refers to spare parts (tire,tube and bearing) 
We are able to meet customer's request

           
    Wheel diameter                  Wheel Width                           Load                              Hub length               Bearing Diameter