Be careful
This product was not what I expected and I was very disappointed in it.  In the past I have bought the entire replacement head which was so easy to install.  This thing is a kits package and is extermely hard to install.  I managed to get two of the three installed.  I well never buy this product again.  The number sh90 is very confusing.  You really don't know that you are getting a kit that you have to install.  If I was a watchmaker I could probably do it. I am considering just going back to a safety razor.
Rating: 1 stars