The Square Lace High Neck sweater dress combines a thick ribbed main dress with waffle chiffon sleeves, lace frills and a necktie. A button closes at the back and the back waist is elastic. Those are different fit zones: stretch mentioned at the waist should not be projected onto the chiffon sleeve or the neck opening.

Check the back-button opening

Ask for a photo with the back button open and a flat measurement of the resulting neck opening. Compare it with a high-neck pullover you can get on without pulling hard at the neckline. The listing does not say whether the button opens only the neck or a longer placket. The necktie is a styling detail until its construction and adjustability are confirmed.

Measure the non-knit sleeve

S lists 15 in across shoulders and 34.5 in chest; M lists 15.5 and 36; L lists 16 and 37.5. Those numbers help orient the bodice, but there is no upper-arm, cuff or sleeve length. Ask for a flat width at the narrowest part of the waffle chiffon sleeve. Do not assume it stretches to match the ribbed dress.

Read the elastic interval separately

The listed waist is 26–34.5 in for S, 27.5–36 for M and 29–37.5 for L. A hypothetical 31 in waist falls inside all three ranges; chest, shoulder and comfortable waist tension decide what to check next. Ask whether the intervals are relaxed-to-stretched garment dimensions or suggested body sizes. All three rows list 42 in length, with no measurement origin, so use a midi you own to check the hem rather than expecting a longer L.