Description
The MA-R4 is the current-generation primary filter for a wide range of MasterSpas hot tubs and swim spas. Built with a 2-inch female pipe thread connection, it seats securely into your spa's filtration housing and is designed to accept the EcoPur® Charge Mineral Cartridge inside — giving your water both mechanical filtration and mineral purification in a single unit.
This is the correct filter for 2025 and newer models in the series listed below. If your spa was manufactured before 2025, use the compatibility list to confirm — many of these models transitioned to the R4 from the MAR1 in recent years.
Compatible Models (2025–Current)
Twilight Series: TS 6.2, TS 67.25, TS 7.2, TS 7.25, TS 8.2, TS 8.25
Michael Phelps Legend Series: MPL 30, MPL 700, MPL 800, MPL 850, MPL 900
H2X Swim Spas: Therapool SE, Therapool D, Trainer 12, Trainer 15, Trainer 15D, Trainer 21D, Challenger 15D, Challenger 21D, Trainer 19D Max, Challenger 19D MAX
Living Healthy Series: LH L5, LH L6, LH S6, LH L7, LH S7
Also Replaces the MAR1 Filter on Older Models
The MA-R4 is the current-generation replacement for the MAR1 filter. If your spa is from the list below and was manufactured before 2025, this is your filter.
Twilight Series: TS 6.1, TS 67.15, TS 7.1, TS 7.15, TS 8.3, TS 8.35, TS 87.3, TS FIT, TS MP
Down East Series: Cape Cod, Exeter, Portsmouth, Somerset, Windsor, Windsor STS
Legacy Series: LW 730L, LW Acclaim, LW Enterprise, LW Enterprise SE, LW Envision, LW Inspire, LW Inspire SE, LW Intrepid
Legend Series: LSX, LSX 557, LSX 700, LSX 800, LSX 800 STS, LSX 850, LSX 850 STS, LSX 1000, LSX 1000 STS, LSX 1050, LSX 1050 STS
Important Note for Pre-2025 Spas
Most MasterSpas hot tubs and swim spas manufactured before 2025 used a female port that accepted a male-threaded filter. Beginning in 2025, that relationship flipped — this MA-R4 has a female thread and is designed for the new male port configuration. If your spa was manufactured before 2025, you may need a thread adapter for compatibility. If you know you need one, it is available for purchase separately on our site. If you are unsure, contact us before ordering and we will confirm the right fit for your specific model and year.
Replacement Schedule
Replace every 12 months under normal use, or every 6 months with heavier use. If you use the EcoPur® Charge Cartridge, replace it every 6 months.
Due to the nature of filtration products, we cannot accept returns on opened or incorrectly ordered items. Please verify your model and production year before purchasing.
