You can get it on her official website. Shipping charges are $ 3 and all the kits cost $ 5.50. It's very fast because they arrived in less than a week.
The Brush Guard are used to dry the brushes due to they maintain their original shape. I have Variety Kit that contains various sizes for different brushes: 1 for brushes such as apply eyes or blend shadows, 2 blush, 2 brushes for applying makeup and 1 for powder or kabuki brush.
Moreover, there are more kits on their website. To dry the brush is ideal as it leaves its original form.
I've loved it =)