Ultimatrix

 The Ultimate Omnimatrix (often referred  to as the Ultimatrix) was the device that Ultimate Alien revolved around. Ben used it to replace the Omnitrix, which he destroyed in a battle with Vilgax. The Ultimatrix was removed by Azmuth in The Ultimate Enemy: Part 2 and replaced by the third Omnitrix.

 Originally created by  Azmuth, the Ultimatrix's  power core  was unstable and incomplete, so he put the device in high  security storage.

Backstory
Albedo stole the Ultimatrix and was able to stabilize the core, as well as "surpassing" the prototype Omnitrix by adding the evolutionary function. Unfortunately for him, Ben's DNA was still the default for the Omnitrix and the Ultimatrix was still linked to the same database, so Albedo only had access to Ben's current aliens, which excluded Grey Matter. Allying himself with Vilgax, he agreed to help him so he could turn himself back to normal, while Vilgax could have the Earth. After Albedo as Ultimate Negative Humungousaur easily defeated Ben as Humungousaur, Vilgax threatened Gwen and Kevin's lives in order to force Ben to give up the Omnitrix. Afterwards, Vilgax betrayed Albedo by using the Omnitrix to defeat him by turning his army of Bioids into thousands ofHumungousaurs.

Later, Ben activated the Omnitrix's self-destruct mechanism to force Vilgax to remove it but Vilgax refused, thinking he was bluffing and later suffered the consequences. Ben released Albedo and forced him to give him the Ultimatrix via the same threat. Ben used Ultimate Swampfire to battle Vilgax and used Jetray to later escape.

Ben continued to use it until he defeated Vilgax with Diagon's powers, Azmuth came to take Ascalon as well as the Ultimatrix and gave the new Omnitrix to the worthy wielder.

Albedo would later create a new Ultimatrix, one that (upon the requisition of a Polymorphic Crystal) allowed him to change from one Ultimate form to another, without changing to regular aliens inbetween.

Description
The Ultimatrix, unlike the Omnitrix, didn't resemble a wristwatch, looking more like a gauntlet. The central component, the selection interface remains the same, while the watch band was replaced by a gauntlet-like band extending up to almost half of the wearer's arm (since the band's ability to morph its shape wasn't placed into it).

When Albedo used it, the Ultimatrix had a red color scheme. After Ben took the Ultimatrix from Albedo, the Ultimatrix became green. This shows that the user can change the color scheme of the Ultimatrix.

The selection interface was identical to the original dial, with the intergalactic peace sign that changes color to reflect what mode the Ultimatrix was in.