Deluxe Spas SL / SM Series 50 sqft filter cartridge

Deluxe Spas replacement filter cartridge. 50sqft

Very unique female fine thread size

293mm H x 215mm OD x closed top x 64mm ID internal thread - bottom.
(Also replaces similar longer filter cartridge approx 390mm long) 
This internal thread size is much larger than any others available and is a unique size that matches no standard fittings.

Used on Chinese made Deluxe Spas sold under various names including Classic Spas
Spa models include:
Deluxe Spas SL-5600
Deluxe Spas SL-5601 or Classic Vanquish
Deluxe Spas SL-7300 or Classic Platinum
Deluxe Spas SM-5300
Deluxe Spas SM-7300
potentially others with SL-xxxx or SM-xxxx

(newer versions of these spas use alternate filters - check dimensions)