Human Ras Binding Domain (RBD) of Raf-1 Proto-Oncogene, Serine/Threonine Kinase (RAF1), (UniProt # P04049, amino acids 50-140), expressed with an N-terminal 6XHis and C-terminal FLAG in E. coli. Specifically binds to and precipitates Ras-GTP from cell lysate. Can be bound to glutathione coated plates prior to precipitating Ras-GTP.