Instruction: Extract information from the supporting document to answer the given question.

Input:
Question: What is the diameter of the pole?
Document: Also, you could position the shelves to hide the seams if you wanted to.The main poles are about 1" in diameter. Then at the top, there's a spring inside the uppermost 1" pole, a cap with a hole on it that fits over that, and then a 1/2" pole that feeds inside the larger pole. The spring provides the tension.
I was looking to replace an existing similar caddy I have, that has served me well. Unfortunately, due to the lack of clear dimensions and pictures, I ended up with this product which is not "large" enough to replace my current one.This one has shelves that are about 7" on an edge, and a 1" pole diameter. This leaves about 5" of space for your stuff... not a lot.
So tall it didn't work in our shower without sawing off some of the pole! Once we rigged it it worked fine.
This product is very cheap and did not last a year. The plastic part of the shelves that rests on the pole breaks off.
Cheap and looks great in the shower. Pole has been in the shower for over a month with no mold or mildew issues.
Had to replace a rusting shower pole and this design is very nice for the money. Shelves are white plastic but are very strong.
Shower pole Did not fit in shower. Cheap materials. Product not as expected. Do not recommend anyone to buy this product
The first one lasted us many years before the pole started to rust, we liked it so much we bought another.
nice product, easy to  set up, only fault i saw was the top of the pole could have used a wider cap,  It.s trying to push through the ceiling
Too short, but with a little ingenuity it works fine. Luckily I have bought this too short shower pole before, so I already had a fix. Very happy with my buy.
Answer: one inch---seal joints of pole with clear finger nail polish from dollar srore