The polo shirt here is three-ply, mostly, which means it is light enough to be worn underneath a jacket, but of sufficient substance to be worn with nowt else. It is hand-framed — i.e. made by a single skilled knitter on a hand-operated contraption, which is how things should be but very seldom are.
The polo has in-set sleeves, but with the shoulder seam pushed forward for a smoother line. This is a tell-tale sign of fully-fashioned knitwear, which is an approach to knitting wherein each piece of the garment is individually shaped and engineered — tailored, almost — for the best shape and fit.
The sleeves of the polo shirt are noticeably thinner than the body. They are two-ply vs. three. This frees up space for layering the polo with, say, a smart jacket the top. With the very same rationale, the sleeves are also a flat plain-stitch, as opposed to the more textured and chunky tuck-stitch employed elsewhere.
The polo is entirely hand-linked — meaning that, where the neck joins the body, or the sleeve joins the neck, there is no discernible seam or bump. Just a flat, smooth, every-tiny loop-of-yarn-looped-by-hand-and-knitting-needle-onto-the-next-one link (as time-consuming and skilful as it sounds).
The polo is made with cashmere-cotton yarn. That's cashmere as in the softest — seriously, the very softest — fibres from the throat and belly of goats in the Gobi desert; and cotton as in Egyptian cotton of the very longest staple. It is pleasantly cool to the touch, feathery soft and slinky, yet durable.
Two yarns at play here — biscuit-y shades of the lighter order. They intermingle both in the plain-stitch sleeves of the polo, and the tuck-stitch of the body (right). The latter is the main event. It is a dense stitch, but springy and breathable. And just look: wonderfully textured is the tuck.