When purchasing a pole, choosing a diameter is a big decision (poles are expensive!) Everyone goes back and forth on what they want. When pole first started in the U.S., the only diameter available was the 50mm (2".) Companies eventually realized that the smaller-handed population needed a different sized pole, so the 45mm (1.75") came out. When I bought my first pole, the only options were 50mm and 45mm. Now, several years later, the 40mm and 38mm (1.5") have come out, making the decision on diameters that much harder! What diameter is for you? Well, that depends on the individual and several factors, which I will discuss.
The 50mm, which I believe is actually 50.8mm OD, is the largest of the diameters. It used to be the standard pole size in the U.S., until recently. A lot of studios have them because they are the strongest of the diameters, therefore they are safer for taller ceilings. They do not have as much flex as the other diameters. This diameter is really good for thigh holds and large hands. Knee holds can be a little harder on this diameter as are tricks in which you wrap your body. I find the inside and outside leg hangs awkward on this diameter since I have a short torso, so wrapping my leg around this pole while avoiding my lowest rib is awkward. I know that girls with very thin legs like 50mm poles for thigh holds. I am short and have meaty thighs. I find thigh holds to be fine, but any other movement to be awkward. Tall girls, with large hands, and males should do just fine on a 50mm.
50mm poles are sold by Platinum Stages, X Pole, Lil' Mynx, and Pole Danzer. They come in stainless steel, chrome, titanium gold, brass, and powder coated.
My hand fully wrapped on a 50mm Gun grip on a 50mm