If you currently have and Accuload II or III, now is the time to start looking to upgrade.
You have two upgrade options...
1) Perform an Accuload III to IV upgrade. The III to IV upgrade entails swapping the ALIII front cover and internal boards with a new ALIV front cover which comes with the new boards already housed in the cover. Going this route reduces the time and expense of swapping out your current preset with a new unit. The new front cover gets bolted onto your current housing and the wiring already in place can remain to be re-landed.
2) Purchase a new Accuload IV. This is your only option if you have an Accuload II.
If you have an Accuload II or Accuload II to III upgrade, this unit will have to be replaced with a complete Accuload IV. Unfortunately the old Accuload II body does not match the new Accuload IV front cover.