The authors present evidence supporting the conjecture that magnetic monopole soliton solutions, as modified by Prasad, Sommerfield, and Bogomolny, form a gauge triplet with the photon. This conjecture implies a Lagrangian similar to the original Georgi-Glashow model but with magnetic charges replacing electric charges. The dual invariance between electric and magnetic charges is preserved in the presence of matter, and the possible charges must satisfy a specific relation. The authors suggest that the field theory of these monopoles should have an H^V gauge symmetry, where H^V is explicitly constructed from the gauge group H. They argue that the classical properties of the monopole, such as its spectrum, mass, and long-range force, are consistent with this conjecture. The quantum properties of the monopole are yet to be calculated, but the classical properties support the conjecture. The authors also discuss the dyon solutions and the dyon mass formula, which exhibit universal features and a continuous symmetry under rotations in the (q, g) plane.The authors present evidence supporting the conjecture that magnetic monopole soliton solutions, as modified by Prasad, Sommerfield, and Bogomolny, form a gauge triplet with the photon. This conjecture implies a Lagrangian similar to the original Georgi-Glashow model but with magnetic charges replacing electric charges. The dual invariance between electric and magnetic charges is preserved in the presence of matter, and the possible charges must satisfy a specific relation. The authors suggest that the field theory of these monopoles should have an H^V gauge symmetry, where H^V is explicitly constructed from the gauge group H. They argue that the classical properties of the monopole, such as its spectrum, mass, and long-range force, are consistent with this conjecture. The quantum properties of the monopole are yet to be calculated, but the classical properties support the conjecture. The authors also discuss the dyon solutions and the dyon mass formula, which exhibit universal features and a continuous symmetry under rotations in the (q, g) plane.