UMIDIGI BISON GT2 | GT2 PRO 5G. UMIDIGI BISON GT2 PRO 5G. UMIDIGI BISON GT2 5G. RAM+ROM ----- BISON GT2 5G: 8GB+128GB / BISON GT2 PRO 5G: 8GB+256GB. Color ----------- BISON GT2 5G: Storm Gray/ BISON GT2 PRO 5G: Hack Black.