Key differences for the 2500 are listed in the feature bullets. 2500 SPN REEL, 2500HS SP REEL, 3500 SPN REEL, 4500 SPN REEL, 4500HS SP REEL, 5500 SPN REEL, 6500 SPN REEL, 6500HS SP REEL, 7500 SPN REEL, 8500 SPN REEL, 8500HS SP REEL & 10500 SPN REEL.
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