Quantum Scalar i6000 User Manual page 60

Chapter 1: Description
Library Features
42
increased to as many as 7,146 LTO cartridges (for a single-robot library)
or 7,224 LTO cartridges (for a dual-robot library).
Expansion modules are sold separately from the slot licensing. This
separation provides the flexibility to order the exact modules needed
(DREM, SEM or HDEM).
Quantum Scalar i6000 User's Guide