Improve traction - With our Worx robot lawn mower spikes, there are no more holes in the lawn, it is easier to ride on hills, 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 Head Screws - 4 x 20mm stainless steel Phillips head screws ensure easy mounting of the mower spikes, and the recessed screw holes allow for a snug fit, so the lawnmower wheels won't get caught 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 satisfaction is our