Climbing or erect herb, stem pubescent, hairs brown, stiff spreading. Leaf trifoliolate, petiole 5-21 cm long, leaflet 5-16 cm long, 3-12 cm broad, elliptic, rhomboid or ovate, the lateral somewhat oblique, entire or 2-3-lobed, acuminate, glabrous or bristly pilose on both surfaces, petiolule 3-6 mm long; stipules 1-1.8 cm long, peltate. Inflorescence axillary, many flowered, peduncle 2.5-9.5 cm long, bracts 4-5 mm long, pedicel 2-3 mm long, bracteoles 4-7 mm long. Calyx tube 3-4 mm long, glabrous, teeth 1.5-4 mm long, ciliate, the upper pair almost united. Corolla greenish yellow. Vexillum 1.2 cm long. Fruit 4-9 cm long, linear-cylindrical, 5-6 mm broad somewhat constricted between the seeds, pubescent, hairs spreading, dark brown, 8-14-seeded.