Murray 20-Inch Lawn Mower Blade 20045 & 42785 MR-20 Arnold/Murray 20-inch lawn mower replacement blade lets you cut, mulch, and edge with consistent precision Together theyll help you make a clean, sharp cut for a neater, healthier lawn Arnold blade accessories give you what you need for installing and maintaining your cutting edge For model 20045 & 42785 MR-20