LONELY BINARY

LONELY BINARY 5-Set I2C 4x4 Matrix Membrane Keypad for Arduino ESP32 Pico | 5 soft keypads + 5 I2C adapters; 16 keys each, 2-pin (SDA/SCL) saves GPIO; 3.3V/5V; adhesive backing; storage case; Pi, STM32

Name: LONELY BINARY 5-Set I2C 4x4 Matrix Membrane Keypad for Arduino ESP32 Pico | 5 soft keypads + 5 I2C adapters; 16 keys each, 2-pin (SDA/SCL) saves
Brand: LONELY BINARY
SKU: B0G2KZW8KX
Price: 19.99 USD
Availability: InStock

By Mike Perry, Hardware Editor · Verified 2026-09-06

Mike Perry has researched PC hardware since 2014, tracking 80+ GPU generations, 50+ retro handheld platforms, and 30+ vintage PC configurations. He synthesises community benchmarks, manufacturer specs, and public forum data into actionable buying guides. View full credentials →

$19.99

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View Current Price on Amazon → Compare to similar single board computers

*Price sourced from Amazon.com. Price and availability subject to change.

Bottom line: The LONELY BINARY 5-Set I2C 4x4 Matrix Membrane Keypad for Arduino ESP32 Pico | 5 soft keypads + 5 I2C adapters; 16 keys each, 2-pin (SDA/SCL) saves GPIO; 3.3V/5V; adhesive backing; storage case; Pi, STM32 is a niche pick — read recent reviews before buying in the single board computers category, priced around $19.99. Compare close alternatives before committing.

SpecPicks Verdict

SpecPicks scored LONELY BINARY 5-Set I2C 4x4 Matrix Membrane Keypad for Arduino ESP32… using a rating × review-volume × price-fit model applied to our editorial and benchmark analysis across the single board computers category. LONELY BINARY's single board computers lineup sits within the broader category mid-tier; price and specs are the deciding factors over brand loyalty here. Mixed or limited buyer feedback at this price point — focus your evaluation on recent reviews that specifically address build quality and long-term reliability, and shortlist one or two close alternatives before deciding.

Common buyer scenarios for single board computers of this kind: matching it to an existing build, replacing a failing part, or upgrading from a previous-generation equivalent. Check the spec table below against your current setup — particularly socket / form-factor / power-rating fields — and confirm compatibility on the Amazon listing before purchase. Prices, stock, and Prime eligibility update directly from Amazon's catalog and may have moved since this page was last verified.

Pros & Cons

Pros

✓ Backed by LONELY BINARY's warranty and support channels
✓ Ships via Amazon with Prime eligibility and the standard returns policy

Cons

✗ Confirm socket / form-factor / power-rating compatibility against your build before ordering
✗ Price, stock, and Prime eligibility update from Amazon and may have changed since this page was last verified

Key Features

【5-SET SOFT KEYPAD KIT (5 KEYPADS + 5 I2C ADAPTERS)】Includes 5 flexible soft 4x4 matrix keypads (16 keys each), 5 I2C adapters to simplify connections, and a storage container — suitable for multiple projects or backups.
【SOFT MEMBRANE KEYPADS WITH EASY MOUNTING】Each keypad has a flexible design with double-sided adhesive tape on the back for attachment to project boxes, desks, or enclosures — for custom interfaces in robotics, security systems, or prototypes.
【GPIO-SAVING I2C ADAPTERS】The included adapters enable I2C communication using just 2 GPIO pins (SDA and SCL) instead of the traditional 8, freeing up pins on your microcontroller. Compatible with Arduino, Raspberry Pi, ESP32, and more.
【WIDE COMPATIBILITY】Keypads and adapters support 3.3V to 5V operation for a wide range of MCUs. Easy to program with libraries like Keypad_I2C for quick setup.
【VERSATILE APPLICATIONS】Use these 4x4 keypads for numeric entry, menu navigation, or custom controls in IoT devices, home automation, smart locks, and educational projects. Soft, responsive keys provide tactile feedback in a compact form.

Full Specifications

Brand	LONELY BINARY
Style	5 Set (Keypads 4x4 16 keys +I2C Adapters)
Material	Flexible membrane keypad
Model Name	4x4 Matrix Keypad Kit
Style Name	5 Set (Keypads 4x4 16 keys +I2C Adapters)
Unit Count	5 Count
Model Number	4x4 Matrix Keypad Kit
Power Source	Wired
Built-In Media	5 × 4x4 soft membrane matrix keypads, 5 × I2C adapter modules
Number of Keys	80
Keyboard Layout	QWERTY
Mfr Part Number	4x4 Matrix Keypad Kit
Antenna Location	DIY electronics prototyping, IoT control panels, Keypad input for microcontroller projects, access control systems, robotics interfaces
Hand Orientation	Ambidextrous
Compatible Devices	Arduino, Arduino UNO, ESP32, ESP32-S3, Raspberry Pi, Raspberry Pi Pico, ESP8266, STM32
Enclosure Material	Flexible membrane keypad
Included Components	5 × 4x4 soft membrane matrix keypads, 5 × I2C adapter modules
Keyboard Description	Numeric
Warranty Description	1 YEAR
Connectivity Technology	I2C Digital 4×4 Matrix Keypad Interface GPIO (via I2C adapter)

Ready to buy?

LONELY BINARY 5-Set I2C 4x4 Matrix Membrane Keypad for Arduino ESP32 Pico | 5 soft keypads + 5 I2C adapters; 16 keys each, 2-pin (SDA/SCL) saves GPIO; 3.3V/5V; adhesive backing; storage case; Pi, STM32 is available on Amazon with Prime shipping and the full Amazon returns policy. SpecPicks earns a small commission on qualifying purchases — thank you for supporting independent review work.

View Current Price on Amazon →

*Price sourced from Amazon.com. Price and availability subject to change.