Improve traction - With our Worx robot lawn mower spikes, there are no more holes in the lawn, it is easier to ride on the mountain and it does not slip on rainy days. 205 mm in diameter and 2 mm in thickness. Stainless steel material - Our Worx robot lawn mower spikes are made of 304 stainless steel and polished in an additional production step to achieve a perfect appearance. All edges of the Worx Traction Enhancer are deburred. Premium Phillips Screws - 4 x 20mm stainless steel Phillips screws ensure easy mounting of the mower tips, and the recessed screw holes allow for a perfect fit of the screws, so that the lawn mower wheels will not be caught by the screw heads. Fits 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] Stainless Steel Material & High