Spa Filter Darlly: 40025-2PK, Baleen: AK-30053, OEM: WM-3779, Pleatco: PBW4PAIR , Unicel: C-4313 , Filbur: FC-3750, Diameter: 4-1/4", Length: 3-3/4"

Filter Specifications:

• Square Footage: 10 sq. ft.
• Media/Thickness: 3
• Diameter: 4-1/4"
• Length: 3-3/4"
• Top: 2-1/16" Hole
• Bottom: 2-1/16" Hole

Equivalent to:

• Pleatco: PBW4PAIR
• Unicel: C-4313
• Filbur: FC-3750
• OEM: WM-3779
• Darlly: 40025-2PK

This Filter Fits The Following Brands:

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