MTD Flat Idler - 280-898 - Replaces 756-0643A / 756-0643 280-898 MTD Replacement Flat Idler Replaces (OEM) MTD 756-0643 and 756-0643A Fits MTD 2002 and newer 600 series models Inside diameter: 3/8"; Outside diameter: 4"; Height: 1 3/8" Flat idler is made with steel material