HTW Campfire fire pit rings are awesome for camping or just the weekend cookout in the backyard. We put quite a bit of time into designing and cutting these with more detail than most put into them. The Bolt together fire pit is for the permanent locations. The Lock together Model is for Camping and those who want fast setup and tear down. It will stack up and only take up 28"x12"x 8" of space. This outdoor fire pit is made from 10ga hot rolled steel, ( When dealing with gauge steel the smaller the number the heavier the steel. Don't be fooled by ones that boasts sturdy construction, Ask what gauge it is. 10ga=.1345". Some boast heavy or sturdy 18ga construction, 18ga=.0478") sand blasted, and coated with hi-temp black powder coat, they are 11.5" tall. These fire pits are prerolled to a 20" radius which makes the 40"ring and can easily setup. 30" and 50" will need some tweaking once assembled to reach a perfect circle. You are going to buy these by the section,/ea. 3ea being the min and 5 being the max.