SIZE: diameter 14"(355mm), 3T, 4mm Thickness, Arbor 1". Arbor 1" with 7/8"-20mm-5/8" circular adaptor washer. UNIVERSAL FIT For Circular Arbor. For all circular arbor equipment brand. SK-5 steel is estimated to last 10x longer life than normal Carbon Steel. Excellent for cutting tough and tangled weeds, undergrowth and light bush with high efficiency. Warning: this blade use for heavy duty working, please use on more than 30cc equipment, It is best to use it on a higher than 50CC.