Thank you for viewing. This is a Yamaha flute head cork. Part number: FLUTE HEAD CORK T33.OXD18.5 I used some of them, so there are 5 in the first photo, but there are actually 4 remaining + 1 half cork. (See images 2 and 3) The half cork was used for the A key cork of a YCL450, so it is half size. The bag has been opened. Please refrain from purchasing if you are sensitive to minor imperfections, as this item is stored by a private individual. I would appreciate it if those who have read this description carefully would consider purchasing.