These microdermabrasion crystals are used in micro-dermabrasion machines by health practitioners and clinics in the UK for all microdermabrasion applications. Kindyco microdermabrasion crystals are available in single 100, 120 and 120/150 mixed grit size. The most frequently used Aluminium oxide grit particles for the majority of micro-dermabrasion units are the 120 and 150 grit sizes.