The W-A4 model is developed with Irish music in mind. It has wooden ends with metal inserts for the primary reflection areas. The reed pans are parallel.
The W-A4 is available with Vintage type parallel reeds (standard), or the Wakker tapered reeds (optional).
The Wakker reeds option consists of long scale tapered reeds, with better reed scaling (more reed frame sizes for the same compass) which results in a more powerful tone and better balance. 
The standard A4 configuration has hardwood flat ends and nickel plated metal inserts.