You can use the inventory system and actions to attach and swap compatible items to clothing that you are wearing.
ECH helmet with attachments
If you are wearing an item of clothing that has slots compatible with an item that is available to pick up either from the ground or Arsenal simply approach it and use the actions that pop up or use the inventory and drag and drop them into the item of clothing.
Attached ECH items visible in the inventory
Currently compatible item types (attachment slots vary):
Clothing Type
Attachable Items
Helmets
NVG
Balaclava
Headsets
Strobes
NVG Battery Packs
Velcro Patches
Action to replace one balaclava with another
You can even add patches to appropriate velcro areas. Also, using quick actions you can grab items that are attached to clothing items that are laying on the ground (e.g. grabbing NVG directly off another helmet).
LShZ-1+ with RHS 20 Year patch and NVGs
To remove the items, simply remove them from the inventory slots of the clothing item, or alternatively use the radial menu to detach quickly.
