Section 6(4) in The National Highways fee (Determination of Rates and Collection) Rules, 2008
(4)Any driver, owner or person in charge of a mechanical vehicle who opts for the installation of on board unit (transponder) or any other such device for payment of fee, shall deposit a refundable security equivalent to the cost of the equipment with the Central Government, the executing authority or the concessionaire, as the case may be, for such installation and no interest shall accrue on such security deposit.
