PS2 Laser Lens SF-HD7 can correct the below problems:  

Your games are taking much longer than before to load;

Your PS2 is having trouble reading certain games;

Watching DVD's is a pain owing to flickering screens and jumping scenes ;

System shows a message "Disc Read Errors" or disc appears damaged or dirty on the screen;

It suports: V9, V10 & R: - 30001 / 2 / 3 / 4 R- 30005 / 6 / 7 R- 39002 / 3 / 4- 50K (SCPH 5000x).

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How to identify what PS2 version console you have?
The version 1, 2 and 3 PlayStation 2 all have 10 screws on the bottom of the unit.
SCPH30001 v1 = Serial# begins U1
SCPH30001 v2 = Serial# begins U0
SCPH30001 v3 = Serial# begins U1 Date 1A
SCPH30001 v3 = Serial# begins U2 Date 0D

The version 4, 5, 6 and 7 PlayStation 2 all have 8 screws on the bottom of the unit. The 4 and 5 also have the electrical warning stamped on the bottom of the PlayStation 2 case.
SCPH 30001 v4 = Serial# begins with U0
SCPH 30001 v4 = Serial# begins with U1
SCPH 30001 v4 = Serial# begins with U2
SCPH 30001 v4 = Serial# begins with U3
SCPH 30001 v4 = Serial# begins with U4
SCPH 30001 v4 = Serial# begins with U5
SCPH 35001 v4 = GT3 Edition

There are 3 different motherboards for the SCPH30001R - Version 4, 5 and 6
SCPH30001R v5 or v6 Motherboard
SCPH39001 v7
SCPH50001 v9 or v10

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