RSD Crossed roller sets typically consist of: 4 rails, 2 roller/cage assemblies + 8 end screws
All of the components necessary for 1 axis of motion. This is the industry standard crossed roller geometry and is usually dimensionally interchangeable with most other popular crossed roller products. Accuracy or Precision Grades range from:
SP (or Q8) - Standard Precision Grade (most common)
HP (or Q4) - High Precision Grade
SF - Super Fine Grade
KZR cage is plastic and AA cages are steel and rollers are retained.