Today at the local supermarket i found a pack of ten cartridges blades (with goo strip) saying they will fit Trac II and Atra heads among others (Pivot), i was surprised because i've heard about them but here it's the first time i saw this particular pack...They are made in USA. Can anyone tells me more about them? How they perform and who's the manufacturer (ARC?) A pack of DE made in Israel were there too...