Ace3DS X works on 3ds v11.17 and it has a switch for 3DS ntrboothax mode and DS mode, with a small magnet

switch down is DS mode, switch up is ntrboothax mode, the default is down DS mode.

Ace3DS X is a perfect substitute of R4I GOLD 3DS PLUS card, same functions. 

It can play nds games and flash ntrboot B9S.

What is included?

It include: 1.Ace3ds X card + 2. micro sd card reader + 3. a small magnet

Ace3DS X supports 3DS Ver. 11.17.0-50.

There's a NTRboot loader switch, you can learn how to do it from the official website.

FEATURES

• Hardware: Ace3DS X has a switch for 3DS mode and DS mode
• 3DS mode-NTRBOOT flashed FLASHCARD. Ace3DS X has been pre-flashed NTRBOOT and supports installing boot9strap on all 3DS consoles models & versions
• The using method of Ace3DS X is a little different from other flashcards, and you need to insert one FAT32 microSD card(maximum capacity is 128GB) to your flashcard
• The other steps of using Ace3DS X are the same as other flashcards. Follow the Installing boot9strap (ntrboot) instruction in 3ds.guide.
• https://3ds.guide/installing-boot9strap-(ntrboot)
  
• Change the step 3 as: Insert one FAT32 microSD card(maximum capacity is 32GB) to your flashcard, then insert your flashcard into your device
• DS mode. It is ace3ds plus, the using method is the same as before.