Spatial distribution of RR Lyrae variable stars detected within 12′ of the centre of Patchick 99. The magenta points represent the seven RR Lyrae stars considered cluster members, whereas we highlight the PM members with magenta squares. The distance error bars are of 0.5 kpc for each point. The dotted line depicts the heliocentric distance at D = (6.4 ± 0.2) kpc derived from the VVV near-IR photometry.