Section 105(4)(iii) in The Central Reserve Police Force Rules, 1955
(iii)by transfer on deputation (by promotion) of Inspectors on the select list for promotion to the posts of Deputy Superintendent of Police or equivalent posts in the State Police or substantive holders of the posts of Inspector or equivalent posts or officiating Inspector with at least three years' continuous service in that grade or equivalent posts in any Central or State Police Organisation preferably with the experience of Armed Police; or