This newer batch of 4-in-1 RF modules, manufactured from dark blue vetronite board, bears the "YRF03_v1.1" mark silkscreened on back. It's again different from the November 2018 upgraded module shown on Deviation's «Devo 12s 3in1 / 4in1 RF module neat installation», page 70.
perfekt, and good priced, i love it