This luxury blazer from Isaia Napoli is tailored from a lightweight seersucker wool blend fabric that can be worn comfortably in warm weather.
Navy blue seersucker wool-blend fabric.  Lighter weight.  80% wool, 19% silk, 1% elastane.

Labeled a European size 54R / US size 44 Long.  Actual measurements:

Chest -  22.5"  underarm to underarm
Shoulders -  18"   across seam-to-seam
Sleeves -  27"   from shoulder seam to cuff
Waist -  21"   across
Length -  30.5"   from bottom of collar


Note - the fabric at the underarms has some pilling from being worn under a snug coat (see photo).  Not visible unless your arms are raised above your head.  Otherwise in very good condition.  Labeled a Regular length but fits like a Long.