You are Purchasing (1) 3/4" X 1" Barbed Coupler that fits 1" OD , 3/4" ID Clear Hose on one side and 1 1/4" OD , 1" ID on the other side. These are used for connecting Clear Hoses together in Hot...
This part is (1) 1/4" X 3/8" Barbed Coupler that fits 3/8" OD , 1/4" ID Clear Hose on one side and 1/2" OD , 3/8" ID on the other side. These are used for connecting Clear Hoses together in Hot Tubs...
This fitting is a 90 degree glue in style spigot x barb. The Spigot side will glue into a 1" fitting that measures about 1 1/4" Inside Diameter and the barb accepts a 3/4" inside diameter hose...