Dryer ball

[1][7][5] The efficacy of plastic dryer balls was disputed by Popular Mechanics who, in 2009, published experiment results in which staff were unable to find any beneficial effects.

[8] Dryer balls are touted to be environmentally friendly for varying reasons versus conventional fabric softeners.

[1][3][5] Conventional softeners primarily function chemically, employing quaternary ammonium cation or stearic acid, which is either suspended in liquid or applied to polyester in the case of dryer sheets.

[3][6] Wool dryer balls are typically biodegradable, however can sometimes be chemically altered or bleached, reducing eco-friendliness.

[1][7] Dryer balls are sometimes touted as hypoallergenic[1] or better for those with sensitive skin[5] as they typically do not apply artificial softening agents or fragrances to clothing.

Two dryer balls
Four spike-covered blue rubberized dryer balls sit in a line in the bottom of the metal drum inside a clothes dryer.
Four spiked rubber-type dryer balls sitting in the bottom of an empty dryer
A large pile of multicolored felted wool balls sit in a basket below a sign labeling what they are and their uses.
Pile of different colored wool dryer balls retailing in Vancouver, Canada in 2011. A sign above purports benefits for the balls.