... Body, Chrome Plating 3. 1/2" , 3/4" for dry hydrant system 4. wall side, pendent, upright open orifice sprinklers for dry ... , such as when a predetermined temperature has been reached.Open orifice sprinklers are only used in water spray systems or ... based, with the heat sensitive operating element removed.Product name: open orifice sprinklers , orifice sprinklers , sprinkler heads for automatic fire ...