Complex sentence: Recently Villeroy & Boch have included saunas and spas/hot tubs to their product range with their spas featuring a system where most of the plumbing is within removable and interchangeable seats.
Split into simpler sentences: Recently Villeroy & Boch have included saunas and spas/hot tubs to their product range. Their spas feature a system where most of the spa plumbing is within removable and interchangeable seats.