There are several ways a piece of gear can be used in Commlink:
CARRIED - The item is directly put in the inventory
EMBEDDED - The item is an accessory to another ite,
IMPLANTED - The item is part of the characters body and costs essence
As a default, Commlink assumes that an item is CARRIED.
If you want to replace this assumption, you can use the <usage> element
<!-- Item is carried (default) --> <usage mode="CARRIED" /> <!-- Item wants to be placed in a specific slot (and fills it totally) --> <usage mode="EMBEDDED" slot="UNDER"/> <!-- Item wants to be placed in a slot and occupies capacity --> <usage mode="EMBEDDED" slot="HEADWARE_IMPLANT" value="2"/> <!-- Item is implanted an consume essence. The essence cost depends on the rating --> <usage mode="IMPLANTED" value="$RATING*0.1"/>