There are also other blades from different brands that fit the preference of your lawn mower. That is very normal, it actually gives you more options to choose form, but be very careful when choosing one, try not to pick lawn mower blades made out of pot metal because it is very dangerous and it has the highest tendency to break. Be sure to only pick hardened steel lawn mower blades. These type of blades are tougher and can be sharpen many times after it has became dull, so you wouldn't have to buy a new one, it's pretty much economic.