likely 39cm collar

You also have a buttonable rear vent

One Size  Fits All

"Luutnantti" Rank Cuff Laurels

Can't see any holes on the piece

British RAF PTI Vest - Medium 102cm Pullover likely 39cm collarAt a glance 100% Cotton Material PTI Patch Great Retro Style Vest Design White w Light Blue Edging Chest Size: 39" Estimated Size: Medium Regular Label reads 102cm Collar to Hem: 29" Modern Militaria Issued Mid 1990's Genuine British Army Surplus MOD Surplus Grades Grade 1 Great condition, some prior use but over all in great shape. Some ever so faint markings from prior use which won't notice if worn tucked in, but certainly ready for much more wear.