CREATE TABLE table_203_253 (id NUMBER, "model" CLOB, "frame" CLOB, "years mfg'd" CLOB, "caliber ( s ) " CLOB, "production" CLOB, "barrel" CLOB, "notes" CLOB)

what was the last year of manufacture for these revolvers ?
SELECT MAX("years mfg'd") FROM table_203_253
SELECT MAX("years mfg'd") FROM "table_203_253"