Per slot license to support full L3 route scale and L3 VPN features on MX2K-MPC8EQ-B. To upgrade MX2K-MPC8EQ-B to MX2K-MPC8EQ-RB mode two licenses have to be purchased – one S-MX2K-MPC8EQ-IR and one S-MX2K-MPC8EQ-R.