I need to clean some exterior slate tiles

[WetSaw]

I've got a client with a slate entrance and terrace that needs cleaning. I went into my local hardware store and asked "Do you have a cleaner for slate?" and was given this...

Well I suppose I got what I asked for..
Good to see a fully labeled package with all the instructions and warnings you could want!

 

[Lithofin BOB]

Only slightly illegal 😵!!!!!! Got a bath tub of the stuff out back has he.