This motor allows you to focus the telescope electronically, instead of manually. A motorized focuser lets you have much steadier high-powered viewing, because the possibility of bumping or shaking the telescope when focusing is eliminated. The motor speed is variable, and also makes fine focusing a snap(which can otherwise be difficult manually).
Long Battery Life
Single 9-volt battery(user-supplied) yields many months of normal use
Low Weight Makes Easy Use
Does not necessitate the use of counterweights on equatorial mounts
Built-in slip-clutch mechanism prohibits damage from exceeding focuser's travel