This 3/4" elbow with a 1/4" barbed nipple coming off of the curve of the elbow is most often found on the suction side of the Silentflo 5000 and 5002 circulating pumps The 3/4" x 3/4" x 1/4" bleed line fitting has a 1/4" nipple (30598) for the 1/4" vinyl ...read more