Flat Responsive Shopify Theme is Premium Template. It's Clean, simple, and the emphasis on your product, and the buying options. There is a ‘zoom’ feature on the main image, and a ‘lightbox’ on the thumbnails, allowing easy browsing.
It has included a ‘Related Products’ block at the bottom, so the customer always has somewhere to go.
Flat Responsive Shopify Theme (DEMO & DOWNLOAD)