The navy stand-collar sports jacket has two narrow pale bars along each sleeve in the current gallery, a front zip and a close-looking elastic hem. It is shown over a dark inner top and light trousers; those other pieces are not identified as part of the jacket order. Its M–XL chart gives chest, sleeve and length, but the shoulder column contains only slashes. That blank column changes how to read the listed 74–79 cm sleeve values: without a starting point, they should not be compared directly with the ordinary shoulder-seam-to-cuff number on a different jacket.

Measure sleeve reach from the same point

Put on a jacket you own with a similar relaxed shoulder shape. Measure once from its shoulder seam to the cuff, then once from the center back neck across the shoulder to the cuff. Label the two readings rather than assuming they are interchangeable. The MAXCT chart lists sleeve 74 cm for M, 76.5 cm for L and 79 cm for XL, but does not define its origin. Ask for the endpoint convention and a flat shoulder or neck-to-cuff photograph with a tape measure. The gallery suggests a relaxed upper sleeve; it does not establish where the seller began measuring. A reported 2.5 cm step between sizes is arithmetic, not proof of where the cuff will land on your arm.

Zip the reference jacket before judging chest room

Try your reference jacket over the shirt or knit you intend to wear. Zip it fully and reach forward, then sit down. Record whether the chest pulls, the hem rides up or the collar feels crowded. The MAXCT source increases chest by 4 cm and total length by 2 cm at each step. If a reference jacket needs more room only at the waist or hem, the published chest number alone will not answer that problem: there is no closed hem circumference or waistband stretch measurement. Ask for those if you plan to zip the jacket over a thicker layer.

For a worked comparison, suppose your reference jacket has a comfortable 124 cm finished chest and its cuff reach is right, but its 65 cm length ends higher than you want. The listing’s L row has 124 cm chest and 65 cm length. XL adds 4 cm to chest and 2 cm to length, while the sleeve figure rises 2.5 cm by an undefined route. That may change both the fit and the cuff placement; it is not a clean length-only adjustment. Compare the reference from matching endpoints, then ask which dimensions matter most for your use.

Separate the visible details from performance claims

The source lists 83% cotton and 17% polyester and a Navy Blue option in M, L and XL. It does not state fabric weight, lining, weather protection, stretch recovery or care instructions. The stand collar and sleeve bars are visible styling details; they do not establish warmth or athletic performance. Check the actual variant photo for color and stripe placement, then finish the purchase decision with the sleeve origin, zipped hem and reference-layer measurements resolved.