Layer Estimates:

Layer: Allegheny County Block Groups (ID:0)
Count: 1062
Extent:

XMin: -8945723.94216758
YMin: 4894216.69700586
XMax: -8870936.47556994
YMax: 4964513.41979762
Spatial Reference: 102100 (3857)

Layer: B15003_Block_Groups (ID:3)
Count: 1062

Layer: B23025_Block_Groups (ID:4)
Count: 1062

Layer: B02001_Block_Group (ID:5)
Count: 1062