Li2B4O7 is used as a filter for small PHS and key-less entry due to its temperataure stable feature(zero temperature coefficient of frequency).
Since the crystal is deliquenscent, it requires a technology such as atomospheric control for storage and device production. 

3 inches diameters with length from 40mm to 120mm are available.LaserMa can supply the products in the forms of boules, wafers as well as slices upon your requirement.