Top 21 is the biscuit joiner from the inventor of the Lamello System and includes a height adjustable blade for cutting the 4 mm groove. The unique height adjustment of the cutter in steps from 0.1 mm to max. 4 mm allows positioning the groove in the middle of the material thickness. Precision in every component leads to perfect accuracy of the workpieces and saves time. The multifunctional stop square allows perfect mitres by applying on the exterior surface and stabilises the machine in vertical position.