WP-Quadra - 3 Layer Plank Product. The plank appearance is emphasized thanks to bevelling of the longitudinal and header joints. Tongue and groove joints on four sides. Can be completely adhered to the subfloor. Also suitable for floating installation in optimal room climates. Tailor made and dimensionally stable header joint by utilizing top-quality plywood. Spruce supporting material with vertically arranged growth rings. Suitable for use over underfloor heating.