T41 Inside diameter: 4.1mm, L/M/S
T55 Inside diameter: 5.5mm, L/M/S
The T41 is suitable for Earphones with a catheter diameter (widest) of 4.4-5.8 mm.
The T41 is suitable for Earphones that use a single moving coil unit such as KXXS/Spaceship/Starfield/MiRai. (Unspecified Earphones can consult customer service).
The T55 is suitable for Earphones with a conduit diameter (widest) of 6-7mm.
The T55 is suitable for Earphones with multiple unit designs such as the S8/Solis/Blessing 2/A8. (Unspecified Earphones can consult customer service).