The following circuit board(s) are compatible with the above topside: 59-553-1000
On 10/7/2009 United changed the type of connectors for the topside and the transformer from a RJ45 to 8 pin Molex and in 2012 changed to a 10 pin Molex. ;If you are replacing just a board or topside insure you have the correct topside adapter cord for your configuration:
🔧 Parts and fittings for this
| Part | Our part number | Availability | |
|---|---|---|---|
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Adapter Cord, 10 pin Molex to 8 pin Molex | EL137 | 2 in stock |
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Adapter Cord, 10 pin Molex to RJ-45 Phone | EL138 | 2 in stock |





