ATVATP Pack of 2 Oil Seal for STIHL 017 018 021 023 025 MS170 MS180 MS210 MS230 MS250 Chainsaw Pack of 2pcs Size: 15x25x5 Replacement part number: 9638 003 1581 Fits STIHL 017 018 021 023 025 MS170 MS180 MS210 MS230 MS250 chainsaw