Universal - use with all hanging feeders up to 10 lbs. Lets consumers use feeders they already own. Economical - retails for 33%-50% less than most other anti-squirrel devices. Safe - does not harm birds or squirrels. Durable - weather-resistant PVC. Easy to use - no assembly required. No need to purchase "special batteries" - operates on three standard "D" size batteries (batteries not included). Smart technology prevents motor fatigue. Feeder sold separately.