|Note_en= Advertising for the [[Parker 51]] model priced $12.50 and $15.00 in ''Black'', ''Cordovan Brown'', ''Blue Cedar'', ''Dove Gray'' colors. Mention the [[Advertised Feature::Parker 51 Ink]]. Brief mention for [[Vacumatic]] models at $8.75. Appears the ''[[Blue diamond]]'' | |Note_en= Advertising for the [[Parker 51]] model priced $12.50 and $15.00 in ''Black'', ''Cordovan Brown'', ''Blue Cedar'', ''Dove Gray'' colors. Mention the [[Advertised Feature::Parker 51 Ink]]. Brief mention for [[Vacumatic]] models at $8.75. Appears the ''[[Blue diamond]]'' |