This pack includes a total of 27 bases in various sizes: 40 mm x 40 mm square (27 pieces), 20 mm x 20 mm square (12 pieces), 20 mm x 80 mm rectangular (3 pieces), and 20 mm x 40 mm rectangular (6 pieces). The bases are designed for compatibility with multiple miniature collections and wargaming systems, including fantasy, sci-fi, and historical settings. They can be used with popular tabletop games such as Black Powder, Hail Caesar, Dungeons & Dragons, and Warhammer 40K. The larger bases accommodate bigger models, while the smaller sizes are suitable for basing individual figures or grouped units.