Primaplus compression fittings are a premium brass fitting, manufactured in Britain and fully WRAS approved. They are made to EN 1254 standard, ensuring a perfect fit. PrimaPlus fittings are also kite marked, signifying adherence to the highest British standards. This product is WRAS approved for use with drinking water and manufactured to BS EN 1254-2. The spanner size is approximately 30mm. Please note BSP thread dimensions are 1/4 inch larger than stated; therefore, a 3/4 Inch BSP thread measures 1 Inch in diameter. For a 3/4 Inch diameter thread, you require the 1/2 Inch version.