The speed of reverse converters in Residue Number System is one the most important and effective factors which is strictly dependent on the selected moduli set. In this paper, the four-moduli set {2^n+k, 2^2n-1-1, 2^n/2+1, 2^n/2-1} is introduced with flexible dynamic range 4n to 5n where n is even and k<n. Then a high-speed two-level architecture reverse converter is designed for it based on mix-radix conversion (MRC) algorithm. A comparison to the similar recently introduced moduli sets {2^n/2-1, 2^n/2+1, 2ⁿ+1, 2²ⁿ⁺¹-1} and {2²ⁿ, 2²ⁿ⁺¹-1, 2^n/2+1, 2^n/2-1} shows that the proposed reverse converter has more conversion speed.