You need the TB3 to TB adapter:
TB3 to TB adapter
Then you need a TB cable, this is a pretty good one:
TB Cable
Thunderbolt 2 and 1 are the same for this purpose.
If you already have a TB cable, then all you need is the adapter listed up top.
Unfortunately all things Thunderbolt are quite expensive and they pretty much have to be labeled as Thunderbolt (not USB-C or MiniDisplayport for instance) to work as expected.
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