Direct replacement to your old unit. Plug-and-play, direct fit, easy installation. Within 18 months your shaver will cut an average of 600000 hairs. When completing this substantive task, the cutting part will gradually wear away, and your shaving may become less compact and comfortable. Therefore, we recommend that you replace the metal foil and blade of the razor every 18 months to maintain the maximum performance of the razor and facilitate your efficient shaving every day. Clean the razor before installing. Make sure well your razor model first. Compatible models: For 3 series models:310,330, 340,199, 197s-1, 195s-1199s-1473 5473 6473 7474 5477 5483 5484 5487 5487 6571 3571 4549 1549 2549 3549 4574 3574 5574 2747 5749 3749 7, 7 504750 5751 0751 1751 4751 5751 6752 0752 6754 0754 6756 4757 0763 0764 0765 0766 4768 0769 0776 3776 5778 3778 5779 Colour:Black Material:Plastic+Metal Package Contents: 1 * Replacement Foil 1 * Cutter blade