This is a 100MeV electron linear accelerator designed for injecting beams into the 1.3GeV Booster Storage Ring (BST Ring). Constructed in 2012, it operates independently from the high-intensity electron linear accelerator that supplies beams to the first experimental room. It consists of two 3-meter-long S-band accelerating tubes and a dispersion section. In addition to the transport line to the BST Ring, this electron linear accelerator also includes two beamlines, one for beam diagnostics and another for beam deflection.