I have gained this unit 11 years ago for 180 DM. Meanwhile I cut with this device my 3 children's hair. A good hairstyle has almost 100%. Because can not do much wrong. Simply the hose to the vacuum cleaner, plug power supply; Attach the desired length essay and off you go. The hair is cut ready within 15 minutes. There is no Sauerrei because the hair is drawn equal in the vacuum cleaner. Now after 11 years you would have to renew the knife. Knife Set will cost 40. What is this compared to the cost at the hairdresser. Those who want to save money this is your place.