Installation speakers can include two different types of speakers, those that are intended to be permanently installed indoors, and those designed for outdoor use. Installation speakers for outside use typically have some extra precautions taken during the manufacturing process so they can take the abuse of hanging outside, year in and year out.
Installation speakers can be either low impedance (8 or 4 ohm) or they might be designed for use on a distributed line (70 or 100 volt). Give us a call toll free and we will be happy to explain the differences between the various types of installation speakers.
Another consideration, is that many installation speakers do not come with mounting provisions. Since they do not know how you intend to mount them and where, the manufacturers make you buy the mounting brackets as an add-on. Isn't that nice!