The Package content description in the Item fulfillment record can be printed in Packing slip as follows.

<#assign packagedescription=" "/>
<#list record.packageups as pkg>
    <#assign packagedescription = packagedescription+","+pkg.packagedescrups/>
  </#list>
<#assign packagedescription= packagedescription?keep_after(",")/>
${packagedescription?replace(",", "<br />")}