Kautilya's Arthashastra 2.33.4

2.33.4

tasmād ekāntarāvarā āṣaḍantarād iti sapta rathāḥ //

The best chariot shall measure 10 purushas in height (,i.e., 120 angulas), and 12 purushas in width. After this model, 7 more chariots with width decreasing by one purusha successively down to a chariot of 6 purushas in width shall be constructed. He shall also construct chariots of gods (devaratha), festal chariots (pushyaratha), battle chariots (sángrámika), travelling chariots (páriyánika), chariots used in assailing an enemy's strong-holds (parapurabhiyánika), and training chariots.