Tambar vel is a large shrubby climber, 10-20 m long. The stout stems twine and climb to tree tops. Alternately arranged ovate leaves are 6-15 cm long. Flowers occur in branched, many-flowered cymes. The 8-10 cm size flowers are broadly bell shaped. The flowers are white to pale violet, with a deep purple throat. The petals are rounded with crisp margins.