MacFlex Rucksack Core

The MacFlex "Rucksack" Core is a light torso armor, identical to MacFlex Core, but instead colored in yellow. It used to be bundled with the MacFlex "Rucksack" Carryall backpack as a single item, but was later split into separate items when backpacks were introduced as core attachments. It is manufactured by Roberts Space Industries. Aside from the backpack and torso armor, no other MacFlex "Rucksack" variants exist.

In-game description
"Whether you're planetside or in vacuum, RSI's MacFlex industrial armor has you covered. Reinforced plating keeps you safe from environmental hazards while the array of pouches keep your tools accessible. The Rucksack edition comes with a back-mounted hard-shell carryall that provides extra commodity storage options."

Development
The MacFlex "Rucksack" Core is introduced in Alpha 3.7 with the harvestable mechanics. When backpacks were introduced some time later, the backpack part was split into a separate item.