3 90 Degrees Long Elbow Copper Fitting and 2 couplers for 5/8 Inch copper pipe
These are for 5/8 copper pipe fitting. Nominal size 5/8" pipe, actual OD size of 5/8 copper pipe is 3/4". (OD of pipe is always 1/8 larger than the nominal pipe size). So the ID of the fittings are 3/4".