Improve traction - with our spikes for Worx robotic lawn mowers, there will be no more holes in the lawn, driving in the mountains will be easier and it will not slip on rainy days. 205 mm diameter and 2 mm thickness. Stainless steel material - The spikes of our Worx robotic lawn mowers are made of 304 stainless steel and polished in an additional production step to achieve a perfect look. All edges of the Worx Traction Booster are deburred. Premium Phillips Screws - The 4 x 20mm stainless steel Phillips screws ensure easy installation of the trimmer tips and the countersunk screw holes allow the screws to fit snugly so mower wheels won't get pinched by the screw heads. Compatible with all S and M models (not for 2021 models) S300 [WR130E], M500 [WR141E], M700 [WR142E], M1000 [WR143E], S450i [WR101 SI], S4. 50i [WR102SI], S450i [WR106SI], S700i [WR101 SI], M800i [WR111MI], M800i [WG757E], M900 [WG758E], M1000i [WG796E.1], M50. 0 2.0. [WR165E], M700 2.0 [WR167E] Quality service - your