Singer Simanco 489500
Buttonholer Attachment - Slant Shank
Comes with a set of 5 plastic templates (5/16", 5/8", 13/16", 1-1/16" and 1-1/16" keyhole), feed cover plate and a special long mounting screw for attaching the item to the presser bar. Manual dated 1960. Similar to item 489510. US version came in a pink clamshell aka "Jetsons".
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