Better Brew Mashing & Sparging Bag is designed to fit most boilers, but not to float free in the boiler, just in case it comes into contact with the element as the element will melt the mashing & sparging bag by Better Brew.This bag has fine mesh all round and its size is approx:Top Width = 54cmBottom Width = 26cmDeep = 35 cmApprox (the bag is tappered) (measurements taken flat on a table).