Supplying following ceramics:

Beryllia Ceramics
Transparent Beryllia Ceramics

BeO is lightweight, very rigid and has excellent thermal management properties - meaning it withstands extreme temperatures and rapidly dissipates heat better than any other ceramic material. Beryllia's thermal conductivity is ten times greater than alumina ceramics, making it useful in heat producing circuits, such as those carrying high currents or very dense circuitry. Beryllia's low dielectric constant allows improved electrical performance, particularly at higher frequencies.