Set-In Sleeve
A set-in sleeve is a classic sleeve construction with a shaped sleeve cap that is knitted or sewn into a correspondingly shaped armhole for a closer fit.
Explanation
A set-in sleeve gives the most tailored and fitted result of the common sleeve constructions. Both the armhole on the body and the sleeve cap on the sleeve are shaped with gradual decreases and increases so the two pieces match exactly along a rounded seam around the shoulder. This requires more precise calculation than raglan or drop shoulder, but gives better freedom of movement and a more structured silhouette. The contiguous method is a modern technique for knitting set-in sleeves from the top down without a visible seam.