FAA TSO-C91a Approval. Emergency locator transmitter uses standard Duracell batteries (not incl). The lightest smallest TSO-C91a ELT available. Easy to install, requires no aircraft power. ELT includes, quick release tray, portable antenna, external antenna, panel remote control, connecting cables, installation manual. Dimensions: 7.75″ x 2.75″ x 275″. Easily removed from aircraft for service or for portable use. Transmission frequencies:121.5 and 243.0 MHz. 2.5 lbs.