Gymnocalycium cactus (25 cm)
Cactuses are children of light and their place is on the window. The Western window is available for all species. The southern window is for tolerant of hot species, the eastern window is enough for Gymnocalycium. If you only have a northern window or no window sill at all, you should not buy a cactus. Height about 20 cm, pot size 8 cm.