The mastercam is a single stemmed camming unit, it has optimised camming angles, machined cam stops, narrow head design and an ultra flexible stem.

A flexible, single stem unit with an ultra-narrow head width for hard aid or free climbing
Molded thumb piece
13 mm (0.51") Monster Sling webbing (36% Dyneema/64% nylon)
Range Finder tells you at a glance if you've chosen the right size cam for the placement
Optimized cam angle for more outward force
Machined cam stops
Color-coded sewn slings and tubing
CNC machined for much greater precision than stamped or extruded cams
7075-T6 aluminum
Sizes #00-#6
CE/UIAA certified
Rated to 5kN
65.2g