Viola Queen Ultra Magic Rosin (Large) Hand crafted in Minnesota, Magic Rosin comes in 2 formulas: Magic Rosin  3G and Ultra. Ultra provides even more grip and "pop" than the 3G. Both formulas are used by all instrumentalists, though bassists and cellists tend to gravitate toward the Ultra. Premium rosin for violin, viola, cello and bass. 1.5 inches in diameter. 6/10 of an inch tall,