This Proline filter is new, but may have crinkled pleats, or other slight damage. It may not perform as long as a perfect filter, but it definitely has some life in it.
The second photo is an example of the type of defects -- your filter make look different.
Diameter: 152 mm
Length: 194 mm
Bottom: 1½" SAE thread (46-48 mm outside diameter)
Filtration surface: 50 square feet
Number of pleats: 225
To check the size of your filter, measure its length excluding the handle and the male fitting.
Spa manufacturers who use this filter
4Seasons, Aegean, Alps Spa, Aquamarine, Aquazzi, Bullfrog, Barrier Reef, Canadian Spas, Catalina, Charisma, Clearwater, Dakota, Denicor, Dynasty, Esparanto, Fonteyn, Garden Leisure, Gulf Coast, H20, Haven, Hawkeye, Infinity, Islander, Leisure Bay, Leisurerite, Lotus, Millennium, Peips, Phoenix, Procopi, Riviera Pool, Sapphire, Spaform, Spa-France, Sunbelt, Superior, Thermo, Tuff Spa, Viking Spas, Vita Spas, Wellis... and lots of other brands.
Pleatco: PWW50P3 or PWW50 (also compatible with PDY50P3)
Spa France: SF-2C
Aquazzi : V1-01092015
Canadian Spas: KA-10032