CAS 12055-23-1 appears in our catalog under these names: Hafnium(IV) oxide, 99.95%, (metals basis excluding Zr), Zr t, Hafnium(IV) oxide, 99.9% (metals basis excluding Zr), Zr <0., Hafnium(IV) oxide, tech. , Hafnium(IV) oxide, 99.99% (metals basis excluding Zr), Zr <1, Hafnium(IV) oxide, 99.995%, (metals basis excluding Zr), Zr . Offered by: Thermo Scientific (Alfa Aesar). Available pack sizes: 1g, 5g, 25g, 10g, 50g, 100g, 500g, 2g.