The 3-Lens Turret provides a convenient means of changing lenses quickly. Keep the 3 most frequently used focal lengths on the turret and simply rotate the turret to position the desired lens. That's a major convenience compared to mounting and unmounting individual lenses, or using multiple single lens mounts. Lenses of 35mm to 150mm with standard 39mm "Leica" mounting thread can be mounted directly on the turret without the need for individual lensboards.
Note: Some popular lenses are not suited to be mounted directly on the turret, either because the rear lens element protrudes far enough to prevent rotation of the turret or because the mounting thread is larger than 39mm. Adapters are available to allow the use of many of these lenses - please contact us with questions.