KTM 450 top end gasket question

Threw a piston in my 18’ 450sxf and used a Tusk gasket kit (huge mistake leaked coolant into cylinder right away. OEM stuff on the way). But anyways these were in the Tusk kit and I have no idea what they are or where they would go. Can’t locate them on the parts schematic. I threw it together without them. Are these the culprit to my coolant leak? If so where on earth do they go. Didn’t see anything like this during my initial tear down. Thanks in advance