Glass Bubbles are a versatile filler powder. As well as making your resin as light as it can possibly be, they may also be added to resin to increase surface durability and also to improve water resistance. Frequently added to an epoxy resin for a below the waterline repair to a boat hull.
We have successfully added over 200% glass bubbles to our fast cast without too much impact on its strength, however these are usually added to a maximum of 100% by weight. Price is per kilo and will reduce the more you add to your cart up to a full box.