Compatible with SunSun (Sun Microsystems) 304A (HW304A), 304B (HW304B), 404A (HW404A), 404B (HW404B), 602 (HW602), 602B (HW602B), 603 (HW603), 603B (HW603B) canister filters. This o-ring is compatible with the following canister filter models: 304A (HW304A, HW-304A), 304B (HW304B, HW-304B), 404A (HW404A, HW-404A), 404B (HW404B, HW-404B), 602 (HW602, HW-602), 602B (HW602B, HW-602B), 603 (HW603, HW-603), 603B (HW603B, HW-603B) canister filters.
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