Adafruit Monster M4SK

Overview

The Adafruit Monster M4SK is a purpose-built wearable electronics platform designed for creating animated Halloween masks, costume props, and wearable art. At its core is the ATSAMD51 ARM Cortex-M4F processor running at 120MHz with 8MB of SPI flash for CircuitPython libraries and assets. The board drives two 240×240 pixel IPS TFT LCD displays independently — one for each eye — enabling smooth, realistic animated eye effects and custom graphics.

Audio capabilities include stereo line-out, a speaker output (with 8Ω 1W speaker), and a 4-wire microphone input for sound-reactive effects. Three STEMMA connectors provide easy access to digital, analog, and I2C expansion. Three selection buttons and a 9-wire extension cable (for separating the two eyes across a wider mask) complete the core feature set.

The Monster M4SK runs CircuitPython and comes with eye animation code built in. A JST connector supports 3.7V LiPo batteries (420mAh included), making it fully portable. It was originally sold as part of AdaBox 013. The board ships as the PCB assembly with connectors; the full kit also includes the LiPo battery, speaker, microphone assembly, plastic lenses, acrylic holders, elastic band hardware, and blank masks for decoration.