• Common Main Objective (CMO) Infinity Optical System. • 45º binocular head. Dual discussion systems also have 45º binocular head on both primary and secondary units. • All models have widefield eyepieces 10X/FN. 23, except for dual discussion systems which have widefield eyepieces 10X/FN. 21 on primary and secondary units. • Dual discussion systems have a dual observation optical bridge with pointer on primary units. • Power: 110V. UL listed.