Somewhere in another thread someone warned of these expanding and causing possible damage to a stove. While I find it a stretch on the damage issue I have found they will expand. Tonight I did a reload with 3 of the Gren Heat brand brick (they are half size) and 2 regular splits. After the stove was up to cruising temp I noticed the bricks had arched themselves leaving a tunnel right down the middle. Originally they where laid in flat. I went down and read the package and sure enough it says bricks can expand when heated and to not place close to the glass. I will say these bricks do a nice job of lighting very easy and producing a nice hot stove. Also they are the most economic buy in my area. They are right at 210/ton from Rural King. I mostly use them for quick restarts when there is little coals left. I have also used the Eco Brick and the Bio Brick all with similar results.