Oak plank in 3-layer construction with small bevel on long side and approx. 4 mm top layer, with approx. 4 mm backing in the same wood and middle layer conifer. Tongue and groove on all sides for easy installation. For the main part the planks have healthy knots. Stress cracks up to 30 cm, also torn knots and small knots are sealed with appropriate wood putty. Repairs up 25 mm diameter are possible. Small open cracks and unsealed spots of a few millimetres are permitted. Small open cracks and unsealed spots of a few millimetres are permitted. The short boards are already prepared for herringbone laying (77° angle) and are therefore delivered with 50% tongue on the left side and 50% tongue on the right side. The herringbone floorboards are only available with fix dimensions.