Spa Filter Darlly: 40371, Baleen: AK-3048, OEM: N/A, Pleatco: PRB37-IN-4 , Unicel: C-4637 , Filbur: FC-2380, Diameter: 4-15/16", Length: 13-5/16"

Filter Specifications:

• Square Footage: 35 sq. ft.
• Media/Thickness: 4
• Diameter: 4-15/16"
• Length: 13-5/16"
• Top: 2-1/8" Hole
• Bottom: 2-1/8" Hole

Equivalent to:

• Pleatco: PRB37-IN-4
• Unicel: C-4637
• Darlly: 40371
• Filbur: FC-2380
• OEM:

This Filter Fits The Following Brands:

Pentair, Waterway, Rec Warehouse, Morgan, Lifestyle, Maax, Savannah

Filter Glossary

As you can see in this graphic, when looking at a filter's threads from the side the difference is very obvious. Standard, sometimes called "MPT" or "Male Pipe" threads are smaller and have a higher number of threads than the S.A.E. style. The S.A.E. threads are large and are square in nature almost resembling a child's toy.

• MPT: Male Pipe Thread
• FPT: Female Pipe Thread