Standard design diamond anvils have been shown (c.f. M. Seal, High Temperatures-High Pressures, vol 16, pg. 573 ) to have optimum strength.
Normally, these anvils have a fixed pavilion angle of 38 degrees. However, in order to accommodate synthetic type IIac, which are limited to a height of < 2 mm, this needs to be modified accordingly.
Therefore, for synthetic type IIac anvils, we can only supply modified standard design anvils if the girdle is larger than approximately 2.7 mm.