The Leme Tech One is a Smash controller that runs on the proprietary Leme Tech One firmware, which is HayBox-based and HayBox-compatible.
SmallCab offers DIY steel enclosures, such as this one leverless enclosure with 12 buttonholes on top and six more buttonholes in the back.
The DuelPad A16 is an acrylic controller that has 16 buttons with LED support and even comes with a modern console port.
P-3 Controller offers you cases like the Lotus Lever and Lotus Clear—the latter of which is a leverless case.
The Ruyi Box is a stickless controller with 18 face buttons curved quite interestingly as well as two analog sticks.
The button layout of the Meisterbox M from Bavaria is supposed to make it the most ergonomic fighting game controller.
The Haute42 B16 is a larger version of the Haute Board Mini, and this time, it also has more keys, giving it a dual layout.
The SparrowG21 is the final boss of mini leverless controllers—with a plethora of buttons, keys, pins, and even joysticks!