4Pcs/Set Replacement Stainless Steel Knife Blades & Hex Key for Robomow RX ?The stainless steel blade is easy to replace with the supplied screws and the hex key ?It is recommended that you change the blade of your lawnmower once a year ?Robust and sharp stainless steel blade,powerful lawn mower,perfect even for overgrown grass ?Note: ?There may be a 0-1 cm error due to manual measurement. Please make sure you don't mind before bidding. ?Due to the difference between different monitors,the picture may not reflect the actual color of the item. Thank you Specification: ?Compatible Model: For the Robomow RX ?Material: stainless steel ?Length: 11cm/4.33in Package included: ?1 x Blade Replacement ?1 x Hex Key ?2 x Screws