Eliminates insect contamination from bees and flying insects. Has flexible tips that fit on port stems so flying insects cannot enter feeder. One year warranty. Are undetectable by the birds, easy to install and saves nectar. Are the only deterrents that work for pole mounted feeders and flying insects. They reduce rain dilution. Can be used on all droll yankees hummingbird feeders and many others.Size is 12 Pack. Dimensions are 7.25 X 2.75 X 6 UPC Code = 021964104801