This article covers StarTech.com Thunderbolt 3.

Overview

StarTech.com's TBT3TBTADAP is a Thunderbolt 3 to Thunderbolt 2/1 adapter designed to bridge the gap between modern TB3-equipped laptops and older Thunderbolt displays, storage drives, and docks. With a compact 20cm integrated cable and bus-powered operation, it delivers up to 12W of power to connected legacy devices. This adapter is a lifesaver for anyone who invested in an Apple Thunderbolt Display or a high-end TB2 RAID enclosure and now wants to keep using that gear with a newer TB3 notebook. It converts the TB3 signal downward so that TB2 and TB1 peripherals can talk to the host — but only in one direction.

Connectivity & Compatibility

The TBT3TBTADAP connects a TB3 host (laptop or desktop) to TB2 or TB1 devices via its built-in Thunderbolt 2 connector. Compatible host systems include MacBook Air/Pro (2016–2020), Dell XPS 13/15/Latitude/Precision, Lenovo ThinkPad X1/P series, HP EliteBook, and other TB3-certified notebooks. Desktop PCs with a TB3 port also work. Crucially, the adapter's Mini DisplayPort-style connector carries only Thunderbolt signaling — it does not support standard Mini DisplayPort or DisplayPort video. That means you cannot plug this into a regular DP monitor. Thunderbolt 4 (TB4) hosts are not officially supported either.

Product Info

Positioned as a niche legacy-compatibility accessory, the TBT3TBTADAP retails for around ¥5,919 on Japan. It comes with a 2-year StarTech warranty and requires no external power brick thanks to its bus-powered design. The market segment is entry-to-mid: it solves a specific backward-compatibility problem for users who already own TB2/TB1 gear.

Best Use Cases

  • Mac users with Thunderbolt Displays: If you have a 2016+ MacBook Pro and still love your 27-inch Apple Thunderbolt Display, this adapter lets you keep using it without buying a new monitor. One cable handles both video and power delivery. - Owners of TB2/TB1 external storage: High-speed RAID arrays and SSDs from the TB2 era can be connected to a modern TB3 laptop for data migration or ongoing backups. The 12W bus power covers many compact drives. - IT managers in refresh cycles: Deploying new TB3-only laptops while retaining existing Thunderbolt monitors and docks reduces e-waste and hardware replacement costs. This adapter is a cheap bridge. - Not for: Users with TB2/TB1-only hosts who want to connect TB3 peripherals (reverse direction not supported). Also not for connecting DisplayPort/HDMI monitors.

Things to Consider

The biggest limitation is the one-way conversion: you cannot use this adapter to connect a TB3 device to a TB2-only PC. Always verify your host's Thunderbolt generation before buying. Bus power of 12W may not be enough for some larger TB2/TB1 devices — check your display or drive's power requirements. If the device needs more than 12W, you'll need its own AC adapter. For TB4 hosts, consider StarTech's TBT4TBTADAP instead. And if you're connecting to a standard DisplayPort monitor, this is the wrong product — look for a USB-C to DP cable or adapter.

Product Disclosure (Amazon)

  • Manufacturer: StarTech.com(スターテック)
  • Seller: オフィス・モア (in 神戸)
  • Fulfilled by: オフィス・モア (in 神戸)
  • ASIN: B019FPJDQ2
  • Note: This article covers a manufacturer-made product based on Amazon listing details.