Compatible with: For 5643, 5644, 5645, 5646, 5647, 5649, 5751, 5757, 5758. Compatible with the following models: For 51S and similar models, see the description of specific models. Easy to assemble and disassemble: easy replacement without tools. Tip: clean the razor better before changing the head. It is recommended to replace the shaving heads every 18 months to keep them sharp. Color: silver Material: plastic + metal Package Contents: 2 * Omentum 2 * Cutter Head 2 * Cleaning Brush Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in a little different from the real thing. The measurement allowed error is +/- 1-3 cm.