Rite Farm Products blue automatic cup style drinkers with built in trigger and includes the necessary 1/2" PVC fittings to connect it to 1/2" PVC pipe.  Drinker cup is a breeze to clean as it is a quick disconnect orange cup.  1/2" PVC Tee Is slip to slip on open ends, this means you slide your PVC pipe directly into the tee.  This unit will provide many seasons of trouble free use and can be used for many different birds. Cup utilizes a trigger system that automatically fills the cup.  The cup is filled by pecking.  You can design your own drinker system and add as many cups to the PVC pipes as you wish up to 210 drinkers per system.  Drinkers work under low pressure at 5 psi or less.  If you are wanting to hook your water system to garden hose pressure that is fine, but you will need a regulator in order for you to do so.