Made of steel. For mowing tough, dry grass & reeds. Fits FS55R, FS55, FS56R, FS56, FS56C-E, FS70RC-E, FS70C-E, FS80, FS85, FS89, FS91, FS111, FS131, FSA130, FSA130R, FS94RC-E, FS94C-E, FSA90R, FSA90, FS240C-E, FR131T, FR410C-E, FR460TC-EM.