Enlarge / Logitech Signature M650 in the rose colorway. (credit: Scharon Harding) Specs at a glance: Logitech Signature M650 Sensor Optical (model not disclosed) Connectivity options Bluetooth Low Energy or 2.4 GHz dongle Programmable buttons 3 Onboard profiles 0 Lighting None Size Standard: 4.22×2.43×1.49 inches (107.19×61.80×37.8 mm) Large: 4.65×2.58×1.63 inches (118.19×65.65×41.52 mm) Weight Medium: 3.57 ounces (101.2 g) Large: 3.92 ounces (111.2 g) Warranty 1 year Price (MSRP) $40 Other perks AA battery included Logitech Signature M650 $40 at Logitech $40 at Amazon $40 at Best Buy (Ars Technica may earn compensation for sales from links on this post through affiliate programs.) Many mice offer very basic functionality—left-click, right-click, scroll wheel, and not much more.