Original sentence: Old faucet with copper tubings from faucet may be  1/2 female compression.Sometimes old 1/2 might have expanded to 5/8, and may need 5/8 m-comp-1/2 MIP instead of 1/2m-comp-1/2 MIP.The 1/2 m-comp end is for the wall on-off-valve welded tubing.Thus a 1/2 male compression to 1/2 MIP fitting adapter   (1/2 m-CMP - 1/2 MPT) may be needed.or only 1/16" per inch taper
Edited sentence: It has 1 5/8" per inch taper, more than FIP.Old faucet with copper tubings from faucet may be  5/8 female compression.Sometimes old 5/8 might have rusted narrowed to 1/2, and may need 1/2 m-comp-1/2 MIP instead of 5/8 m-comp-1/2 MIP.The 5/8 m-comp end is for the wall on-off-valve welded tubing.Thus a 5/8 male compression to 1/2 MIP fitting adapter   (5/8 m-CMP - 1/2 MPT) may be needed.or only 1/16" per inch taper; Comp has 1 5/8" per inch