Simplicity 6457 Vintage Sewing Pattern, dated 1966.

Juniors' One-Piece Dress in Two Lengths:

Dress with scooped neckline and back zipper has an A-line skirt, empire waistline and set-in sleeves. V. s1, 2, 3 & 5 are regular length. V. 4 is ankle length. V.s 1 & 2 have long sleeves. V.s 3, 4 & 5 have short bell sleeves. V. 1 has contrasting ribbon trim. V. 2 has braid trim. V. 3 has lace edging trim. V.s 4 & 5 have lace edging or braid trim. V. 5 has contrasting skirt. 

Junior Size  13:

Bust  34 inches / 87 cm

Waist 25.5 inches / 65 cm

Hip    35 inches / 89 cm

Pattern is PRINTED, partly cut and checked complete, tissue in good condition. Envelope has paper tanning, wear and tear around opening.

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http://allthepreciousthings.com/collections/1960s