I. PassMe

PassMe is the first passthrough device created. It was made by Natrium 42. It booted in DS mode on GBA slot but only worked with old DS (with firmware from v1 to v3, mostly grey ones).
First design was a bit cheap but some linker companies released one with proper casing.

EZPass

Manufacturer : EZ-Flash

 

Magic Key

Manufacturer : NeoFlash

 

PassKey

Manufacturer : M3 Team

 

PassMe

Manufacturers : Natrium42 / Lynx
Notes : They were assembled by hand and didn't have a real case.

SpriteKey

Manufacturer : Ediy Studio
Notes : Was only distributed in China.

SuperPass

Manufacturer : SuperCard

 

II. PassMe 2

When Loopy discovered there was a way to replace PassMe on iQue DS (Chinese DS) using game headers, those new PassMe appeared.
They work with every version of DS, but need some info about the game you put in the PassMe (so they can't work with every game and need to be reprogrammed for a particular one).

EZPass 2

Manufacturer : EZ-Flash

 

PassCard 2

Manufacturer : M3 Team
Notes : Work with a .dat file on the GBA device to give header information. Still a PassMe 2.

 

PassKey 2

Manufacturer : M3 Team

 

PassMe 2-Z

Manufacturer : www.51gba.com
Notes : This PassMe is bigger than a DS cartridge because it already includes a DS game chip. It's not legit but doesn't need flashing.

 

SuperPass 2

Manufacturer : SuperCard

 

SuperPass 2 Special Edition

Manufacturer : SuperCard
Notes : A newer edition with better shell and easier to use.

 

III. NoPass

NoPass are the new generation of passthrough. They allow any DS (even DS Lite) to boot in NDS mode on the GBA slot.
They have the size of a DS card.
Datel first released their MML and then every linker company released one.
Here follows pictures of the products you can find. They are quite the same and boot on G6/M3/SC...

Dummy Card

Manufacturer : EWin Flash

EZPass 3

Manufacturer : EZ-Flash

 

GD Pass

Manufacturer : GD-Team

 

Max Media Launcher

Manufacturer : Datel

 

MK4-Key

Manufacturer : NeoFlash

 

MK4-Mini

Manufacturer : NeoFlash

 

NinjaPass Media Launcher

Manufacturer : NinjaPass

 

PassCard 3

Manufacturer : M3 Team
Revision : 1 and 2

 

PassKey 3

Manufacturer : EWin Flash

 

PassMe 3 mini

Manufacturer : EWin Flash

 

PassWe 3

Manufacturer : EWin Flash

 

SuperKey

Manufacturer : SuperCard
Revision : 1 and 2

 

Ultra PassKey

Manufacturer : Ultra Flash