Our "special blend" of Cabosil and wood flour used to thicken epoxy. We use this for 95% of our boat building and thickening. The addition of a very fine wood flour at the perfect ratio makes the mix creamier and easier to work with over straight cabosil thickener and it colors the thickener to almost an exact match to okume plywood so if you choose to finish parts of your boat "bright" you won't have ugly white filelts at all the corners. Sold by the pound. A 1 pound bag is approximately the size of a basketball.