I don't know whether anyone uses these or not - I have a few that are available.
All are GRADUAL style, each one in its individual plastic case. Filters are virtually as new.
524 M2
521 G2
527 Y2
523 T2
526 E2 (not perfect)
Also
242 Softener (A)
324 Star 4
$25 for all plus $5 postage ConUS.
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