Brother GTX pro Instruction Manual page 181

(4) Use the clean side of clean stick T to wipe clean the back of the wiper.
Front
Convex part
(5) Rinse the clean stick T in the cleaning cup to use it for cleaning of the exhaust cap to be performed next.
<IMPORTANT>

Be sure to use the clean stick T separately for white ink and color ink.
Precautions to keep good printing quality/use printer over the long term
Clean stick T
Clean stick T
Wiper
Front
181
Wiper
Back
X0322