There are 3 Philips coolskin series. Please check you have the correct replacement head unit. 6700 series - hq167, 7700 series - hq177, hs8000 & hs8400 - hs85.
Philips packaging may differ from amazon display photo
I have used this type of razor for many happy years, I always dreaded shaving but now almost enjoy it. I recently replaced the heads after 2 years, it is as good as new. Certainly would not change to anything else.
I received the product very quickly and exactly as described. Well packaged and worked great on my shaver - has given it a new lease of life! Thanks for an easy pleasant purchasing experience.