File extension: *.ref. Requires additional installation. Link: ftp://h1772544.stratoserver.net/public/Readers/TwinRef%20%28Grass-Telefactor%29/
The Comet-PLUS amplifier is designed specifically for EEG and PSG monitoring labs and combines years of amplifier design and manufacturing experience to provide a completely flexible system. The Comet-PLUS is a compact 57-channel amplifier system. There are 40 AC channels, 4 DC channels, and Pulse Oximeter built into the system..
BESA can read Grass_telefactor (TWinREF) file format.