Brother HL-2440 Service Manual page 172

■ Laser unit serial label
<How to Read>
LUS Model distinction
Frame manufacturer
and mold distinction
T1 the 1st mold
Y3 the 3rd. mold
Polygon motor distinction
<Location>
Serial label
Fig. App. 1-3
Laser unit
Drive sub ASSY
Drive sub ASSY
2 to 10mm
Serial label
Fig. App. 1-4
App. 1-2
Y delay
X delay
Serial number
Inspection machine
Serial label
Confidential