Rex Black Diamond Hot Wax Additive Block. If you've made a 4+1 mix from a package of hot wax and have 7 extra blocks left, you have the option to create another 4+1 mix with just the additive block. Alternatively, you can opt for a highly durable and cost-effective 2+11 mix by adding another black block. The lubricating additives in Rex Black Diamond How Wax are concentrated in a single block, meticulously crafted by hand in the Rex factory laboratory to ensure exceptional quality and unrivaled performance. Each package includes one approximately 40 g piece of wax and an exclusive Black Diamond sticker. Please note that this product is intended for use only in conjunction with the Rex Black Diamond Hot Wax full package.