Renfert’s Aluminium Oxide—most commonly recognized under their Cobra product line—is a premium abrasive sandblasting powder. It is heavily utilized in precision mechanics and dental laboratories due to its high purity (up to 99.7% $Al_2O_3$) and sharply angular grain shape, making it highly effective for cutting and surface conditioning.

25 µm & 50 µm: Used for fine surface conditioning, cleaning delicate ceramic or composite restorations, and preparing surfaces prior to bonding without causing structural damage.