Different slices through the phase space of Agg53 (RSG 7, RSG 8), together with the complete colour-magnitude diagrams (based on Gaia and 2MASS photometry). Top: histogram of parallaxes, excluding the duplicate cluster members. The best fit was achieved with the following double-Gaussian function parameters: ϖ₁ = 1.985 ± 0.010 mas, σ₁ = 0.098 ± 0.010 mas, ϖ₂ = 2.297 ± 0.012 mas, σ₂ = 0.105 ± 0.012 mas. Middle-left: coordinates of the stars in Agg53. Size of the points indicates values of the observed magnitude G. Middle-right: proper motion diagram of Agg53. Bottom-left: colour-magnitude diagram of Agg53, based on the observed values of B_P − R_P and G). Bottom-right: colour-magnitude diagram of Agg53 based on 2MASS photometry. The stars were located using the coordinates in Gaia database.