Supply Kit is a Monthly Quest that is linked to the completion of Daily Quests. Each daily quest you complete contributes towards unlocking Supply Kit rewards.
A number of these rewards can be left unclaimed (within the month), and then claimed during events where those items are required – eg: Chips, Gear Refiner etc. So again – patience is key – Don’t claim rewards until you can gain somethinf from doing so, or at the end of the month.
Additional rewards can be unlocked by spending an amount of money (in Australia it’s $14.99).