Shower draining slowly

[PaulJ9]

I live in a cement slab house so getting to the pipes is difficult at best. The shower is draining VERY slowly and snaking it through the drain itself and the port in the wall have done no good. There doesn't seem to be an external port in the outside wall I can use to snake it there either. Any ideas?

 

[gmartine]

A chemical or mechanical drain unblocker.