Merit's AC Series coil syphons are available in brass, low-lead brass, carbon steel, 304 stainless steel and 316 stainless steel. Standard connection sizes are 1/4" NPT Male x 1/4" NPT Male, 1/2" NPT Male x 1/2" NPT Male or equivalent BSP threads. All syphons are made from seamless (not welded) materials. These syphons are used to reduce the temperature of the process media prior to entering the pressure gauge allowing the gauge to operate within specified process media temperatures.