Please see DFARS 204.7103-1(a)(4)
(4) Single accounting classification citation.
(i) Each contract line item shall reference a single accounting classification citation except as provided in paragraph (a)(4)(ii) of this subsection.
(ii) The use of multiple accounting classification citations for a contract line item is authorized in the following situations:
(A) A single, nonseverable deliverable to be paid for with R&D or other funds properly incrementally obligated over several fiscal years in accordance with DoD policy;
(B) A single, nonseverable deliverable to be paid for with different authorizations or appropriations, such as in the acquisition of a satellite or the modification of production tooling used to produce items being acquired by several activities; or
(C) A modification to an existing contract line item for a nonseverable deliverable that results in the delivery of a modified item(s) where the item(s) and modification are to be paid for with different accounting classification citations.
(iii) When the use of multiple accounting classification citations is authorized for a single contract line item, establish informational subline items for each accounting classification citation in accordance with 204.7104-1(a).