a "weighted shift knob" is a performance driven aftermarket modification which entirely replaces the oem shift knob and sits atop the aftermarket short shifter or oem manual shift stick. initially designed to be used in tandem with a short shifter, it is increasingly being purchased for stock stick shifts. the weight generally varies between 400 and 600 grams or more, depending on the material used. the principle of the weighted shift knob is to make the stick shifter top heavy, thus increasing the throw momentum in order to decrease time between shifts. weighted gear knobs are offered for sale by a variety of north american-based manufacturers in many shapes and finishes, though they are significantly more expensive than the commonly available aftermarket shift knob.