These Kurt Adler twirl-it motor pigtails is a fun, unique way to add motion to your Christmas tree! Each pigtail easily plugs into any incandescent 35, 50, or 100 light set. To hang and twirl your favorite Christmas tree ornament, take off a light bulb from your light set so the Twirl-It can be put inside it. Place any ornament on the hook of the Twirl-It for a spinning motion. When the lights are turned on, the Twirl-It spins the attached ornament. When using Twirl-It with a Pre-lit Tree check your user manual to make sure the tree is lit with Mini-Incandescent Lights, NOT LED lights. Mini LED bulbs are not compatible with this Twirl-It product, but often are the same shape as traditional looking mini-incandescent bulbs.