The EGO POWER+ 21" Select Cut Push Mower delivers the power and performance of gas. The Select Cut multi-blade cutting system is equipped with two， interchangeable lower blades; the mulching blade and the extended run time blade. The mulching blade comes installed on the mower and is ideal for weekly mulching， giving you the mulching quality you would expect from a high-end gas lawn mower. The extended Runtime blade provides an optimal balance of cut quality and runtime for all around performance. Both blades can be used interchangeably based on the desired cut. The EGO Upper Blade is used in combination with the lower blade chosen to slice the grass into fine fragments; this greatly enhances cutting performance with all grass types. Experience Power Beyond Belief without the noise， fuss and fumes. Compatible with all EGO POWER+ ARC Lithium batteries.