The IYRU Fifteen Metre class yachts are constructed to the First International rule of 1907.

A total of twenty 15mR yachts were built between 1907 and 1917, the four that have survived are still actively raced.

The IYRU 15mR boats would replace the YRA 52-raters and open competition to foreign nations, replacing local or national systems with a unified rating system across Europe.

The twenty boats that were built, were raced in Spain, France, Britain and Germany.

In their heyday, Metre classes were the most important group of international yacht racing classes, and they are still actively raced around the world.