Recombinant rat HER2 (ErbB2/CD340) protein expressed in HEK293 cells and supplied lyophilized with a C-terminal 10xHis tag. Apparent molecular weight is ~91 kDa, and purity is greater than 95% by reducing SDS-PAGE. Formulated from 20 mM PB, 150 mM NaCl, pH 7.4, it is intended for research applications such as binding assays, antibody validation, and functional studies. Store lyophilized at -20°C and follow reconstitution guidance.