Outside diameter for RB-Sct-557 gear

order product RB-Sct-557 which is documented to have pitch diameter of 1.5" and outside diameter of 2" however total diameter is 1.5 outside tooth to outside tooth where does the 2 " come into play and what is pitch diameter?

For RB-Sct-557, 48 tooth, 32 pitch aluminum hub gear:

]Pitch diameter: 1.5"/:m]
]Outer diameter: 1.563"/:m]
]Bore: 0.5"/:m]
]Weight: 0.3oz/:m]
]20 degree pressure angle/:m]
]Material: 7075 Aluminum/:m]
]Thickness: 1/4"/:m]
The outer diameter for that gear is wrong and we will update it ASAP.