Has two opposing speakers for balanced sound and better diffusion. Four mounting holders make it easier to install on a variety of vehicles. Lightweight and compact in size, easy to install. Output is circuit, overload, and thermally protected.Features:- Uses advanced DNS/DCR algorithm to reproduce the sound of real engines- Supports two sets of quick-switching engine sounds- Supports AUX channel that can simulate a variety of sounds such as alarm- Allows user to modify, add, or remove sounds.- Supports firmware updates and function upgrades