California Code, Revenue and Taxation Code - RTC § 6369.4

(a) There are exempted from the taxes imposed by this part the gross receipts from the sale, and the storage, use, or other consumption, in this state of items and materials when used to modify a vehicle for physically handicapped persons.

(b) In the case of the sale of a modified vehicle described in subdivision (a) to a disabled person who is eligible to be issued a distinguishing license plate or placard for parking purposes pursuant to Section 22511.5 of the Vehicle Code, there are exempted from the taxes imposed by this part the gross receipts from the sale, and the storage, use, or other consumption attributable to that portion of the vehicle which has been modified for physically handicapped persons.

(c) For purposes of this section, on and after July 1, 2020, and before July 1, 2030, “physically handicapped persons” shall include eligible persons with a severe burn injury, as those terms are defined in Section 3901(1) of Title 38 of the United States Code.