This Proline version filter is new, but is no longer in its original packaging. It filters perfectly well for the moment, but it will not have the same life span as a new and packaged filter.
Diameter: 152 mm
Length (excluding handle and threaded part): 216 mm
Bottom: 1½" MPT thread (46-47 mm outside diameter)
Check that the thread of your old filter matches the photo. If it is "coarser", with more widely-spaced turns, then it is an SAE-type thread and you need a PWW50 filter.
Spa manufacturers who use this filter
Costco, HydroSpa, LA Spas, Sundance Spas
Pleatco : PTL47W-P4
Darlly : SC709 / 60471
Unicel : 6CH-47
Filbur : FC-0315