Hi. Ok, I am officially confused and a little disappointed in the lack of knowledge of behind the counter staff at a local tile retailer. Argh My problem is I try to do a great job and read too much. Haha. I have got my ensuite to a stage read for tiling. The shower tray is in, walls tanked. (I can't remember the brand name of the tanking system) I started reading up on the correct type of adhesive to use in the shower area and come across a site listing British Standard and classes for adhesives. So I thought I needed a D2TE adhesive. I went into a retailer and all three staff just looked blank. When I tried explain, in my limited knowledge, one even said, oh, BS, they're just numbers some guy in an office makes up. At that point he lost all credibility in my eyes. They handed me the phone to speak to a Rep from Mapei. He was much more helpful. I explained the shower setup and informed him I was a absolute beginner, so asked if a standard set adhesive would be better suited to my skill set. He agreed. He suggested Keraflex maxi s1. Standard set adhesive. I was about to look for suppliers when I read that this was a C2TES1. Now I'm confused. 1. What BS class of adhesive do I need and 2. Which products fulfil that specification?