Simplicity 9450; ©1971; Misses' Step-In Dress in 3 Lengths: The step-in dress with princess seaming has front button closing above centre front seam, set-in sleeves and optional purchased belt. Midi length dress V 1 has has top-stitching trim. V1 and 2 have notched collar and long sleeves gathered to buttoned cuffs. V2 is maxi length. Collarless V3 with short, cuffed sleeves is regular length.