From the manufacturer:
Crimson Red is a very vibrant, medium, red tone that works well with all other reds in the line.
It also blends nicely with magentas and yellows to create rich color effects and adds a secondary hue to black and grey tattoos.
This color works great for that satin look when doing any type of roses. This is by far the best red on the market!
Gauge Size
The gauge size is the circumference of the smaller bar in the middle.