Injection-moulded from ABS plastic — the same family of materials used in LEGO bricks. ABS does not warp, holds its shape over time, and bonds reliably with superglue (cyanoacrylate) and two-part epoxy. The textured top surface grips PVA, texture paste, and basing sand without needing to score or rough up the surface first. Takes all spray and brush-on primers cleanly.

Every mould in the OBS range is designed in-house using industry-standard CAD — these are not generic imports. We control the full production chain from design through to quality control. Mould lines are clean and consistent.

Dimensional accuracy is critical for square bases — they need to rank up edge-to-edge without gaps or overlap. The 19.4mm outer width (just under nominal 20mm) gives a fraction of clearance so bases sit together cleanly in movement trays without binding. 2.9mm of underside clearance fits 3x2mm disc magnets for magnetic tray use.

20mm square is the standard rank-and-file infantry base for mass-battle wargaming — the default in fantasy rank-and-flank games, Kings of War, and historical systems from ancients through to Napoleonics. If you're building blocks of infantry for ranked gameplay, this is your base.

The 19.4mm outer width matches industry-standard 20mm nominal sizing with the slight undersize needed for clean ranking. These bases fit standard 20mm square movement trays. OBS square-to-round converters are available if you need to switch between game systems.

Part of the Open Basing System (OBS)

One Ecosystem · Every Size · Every Shape

OBS is a modular basing ecosystem designed as a whole — not a random collection of bestsellers. Every size, shape, converter, and tray is planned to work together. Independent and gamer-built.

New products added regularly — the OBS range is always growing.

Square bases are built to sit edge-to-edge. When basing, keep texture materials away from the edges so bases rank up flush. A clean rim painted in a uniform colour (black, dark brown, or green) gives your ranked units a tidy, cohesive block appearance on the table.

Wash before priming — a quick rinse in warm soapy water removes mould release residue. Let them dry fully before spraying. Batch-prime these on a strip of tape for efficiency when you're doing a full regiment.

Superglue (cyanoacrylate) bonds ABS well. The textured top grips PVA, basing paste, and sand without sliding. For metal models, score the base lightly with a hobby knife for a stronger bond.

2.9mm underside clearance fits 3x2mm disc magnets comfortably. Magnetising a regiment is an investment but makes movement trays effortless — pick up and move entire blocks at once. CA gel, check polarity consistently across the whole unit.