MegaDome cameras currently come with two lens options available:
4.5-10 mm lens (default configuration)
8-16 mm lens (desiginated by -16 in the model number i.e. AV2155DN-16)
Arecont Vision does not recommend attempting to replace the lens with a different lens as you may encounter difficulty focusing or fitting the lens within the dome. The two lens configurations listed above have been tested to guarantee the best functionality of the MegaDome.