Description
Reviews
| Brand | - |
| Category | Robotics / STEM Teaching Tools / Sensors |
| Origin | - |
| Model Number | S21C |
| Operating Voltage | DC 3.3V - 5V |
| Detection Range | 2cm to 400cm |
| Accuracy | ±3mm |
| Beam Angle | 15 degrees |
| Protection Rating | IP67 Waterproof |
| Interface Type | UART / TTL |
| Operating Temperature | -20°C to +70°C |
| Dimensions | 45mm x 20mm x 15mm |
| Application | Robot Obstacle Avoidance |
Anonymous
Mar 21, 2026
Rating: 5/5
Beginner friendly
As someone new to sensors, I found this very easy to set up. The voltage range is flexible, and it worked immediately with my 5V power supply. Great product!
Anonymous
Mar 21, 2026
Rating: 5/5
Reliable in various conditions
I tested this in light rain and dusty environments thanks to the IP67 rating. It maintained high precision throughout. Best ultrasonic module I have purchased this year.
Anonymous
Mar 13, 2026
Rating: 5/5
Excellent value for money
Compared to other high-precision sensors on the market, this S21C offers unbeatable value. The build quality is solid, and the ranging consistency is impressive.
Anonymous
Mar 11, 2026
Rating: 5/5
Perfect for my robotics project
This sensor is incredibly accurate. I used it for a line-following robot with obstacle avoidance, and the response time is instant. The waterproof coating gives me peace of mind for outdoor tests.
Anonymous
Mar 07, 2026
Rating: 4/5
Great precision, easy to integrate
Works flawlessly with Arduino and Raspberry Pi. The documentation could be slightly better, but once connected, the data stream is very stable. Highly recommend for hobbyists.
Anonymous
Mar 07, 2026
Rating: 4/5
Solid performance for smart cars
Using this for an automatic induction car prototype. It detects obstacles smoothly without false positives. Only minor issue is the cable length, which I had to extend myself.
Q: Is this compatible with Arduino Uno?
A: Yes, the S21C module operates on 3.3V to 5V and uses a standard UART interface, making it fully compatible with Arduino Uno and most microcontrollers.
Q: Does it come with mounting brackets?
A: The package includes the sensor module and connecting wires. Mounting brackets are not included, but the module has two standard 3mm mounting holes for easy customization.
Q: Can this sensor detect glass obstacles?
A: Ultrasonic sensors can sometimes struggle with smooth glass surfaces as sound waves may pass through or reflect at odd angles. We recommend testing your specific use case, but adding a textured surface to the glass helps.
Q: What is the maximum update rate?
A: The module supports an update rate of up to 50Hz, allowing for real-time obstacle detection in fast-moving applications like smart cars.
Q: How deep can it be submerged?
A: With an IP67 rating, the sensor can withstand temporary immersion in water up to 1 meter for 30 minutes. It is designed for splash resistance and brief submersion, not continuous underwater operation.
External Round Thread Welding Turning Tool, Threading Tool, Zhuzhou Alloy YT15 YG8 YW2 Lathe Tools, 20*25*30 Square
$17.00
Traditional Children's Rattle Drum, Classic Baby Hand-Shake Instrument, Plastic Toy for Newborn Boys and Girls
$2.90
Ultra-Soft Dual-Tip Blending Stump Set for Oil Pastels & Sketching – Washable Smudge Tools for Shading and Detail Work
$3.39
Chengzhutang Foldable Water Bucket Chinese Painting Brush Washer Gouache Watercolor Paint Cleaning Pail Art Student Brush Basin Collapsible Cup Oil Painting Color Pigment Bucket
$9.80
Meiao Dental Nobel Biocare Import Package - Swedish Dental Implants, Crowns, Abutments, and Dentures
$15,888.00
Outdoor Waterproof ABS Plastic Case - Shockproof Moisture-Proof Storage Box with Cushioning for EDC Tools and Travel
$12.00
Natural Loofah Dish Cloth - Oil-Resistant, Non-Scratch Industrial Scouring Pad
$3.43
Paper Blending Stumps for Sketching - Professional Art Supplies for Highlights, Shadows, Pastels, Oil Pastels, and Colored Pencils - Complete Set for Beginners and Artists
$4.40
Aromatherapy Cup Candle Container DIY Crystal Diffuser Stone Cup Plaster Cement Cup Glass Vessel Demagnetizing Bowl
$4.68
American Chicano West Coast Style Neon Sign - Gothic Script Rap Shop Decor, Opening Gift, Living Room Light-Up Art
$279.00
Data Cable Organizer, Desktop Fixed Charging Cable Storage, Solid Wood Phone Power Cord Clip, Anti-Tangle Adhesive Hook, No-Drill Computer Wire Winder, Wooden Edge Hanging Cable Collector
$35.00
Forest Wooden House Building Blocks - Educational Treehouse Toy for Boys and Girls, Board Game Trendy Blind Box
$12.90
German B&W Safety Case for Folding Knives - EDC Tool Storage Box, Waterproof, Moisture-Proof, Shockproof, Models 1000-3000
$245.00
Fuzao Kids 3D Printing Pen 2026 New Arrival Viral Pretend Play Toy for Girls Educational Gift for Ages 3+ Children's Day
$48.90
UHT Ultra-High Temperature Sterilizer, Room-Temperature Set Yogurt Production Line, Yogurt Processing Equipment, Stirred Yogurt System
$80,640.00
Professional Sketch Blending Kit for Art Students: Gray Tone Pencils, Sponges, Stumps, and Erasers
$4.17
Custom Solid Wood Signboard with Engraved Lettering, Advertising Carved Plaque for Homestays, Tea Rooms, Studios, Wooden Entrance Hanging Sign
$16.90
MOKO Stainless Steel Expandable Dish Drainer - Multi-Function Kitchen Sink Rack for Bowl and Plate Storage
$28.00
WoSporT Factory Direct WST Safety Case 32cm (12.6 inch) - Dustproof, Waterproof, and Impact-Resistant Tool Box
$95.00
South Korea DIO Dental Implant / Implant + Abutment + Crown
$1,580.00
40cm Extended Drill Attachment with Scouring Pad Head for Polishing, Rust Removal, and Marble Countertop Cleaning
$60.00
Authentic Ou Style Tian Kaishu Thousand Character Classic Calligraphy Card for Adult Practice, High-Definition Coated Paper
$55.10
Zer0g Ultra-Light 14g Backpack Waterproof Liner - Polycro Odor-Barrier Pack Liner for Hiking and Trekking
$21.20
Touchmark Liquid Acrylic Markers with Soft Tips, Specialized for Elementary School Art, Ideal Birthday Gift for Children
$18.90
Paper Blending Stump for Sketching - Professional Art Tool with Blade for Highlights, Pastels, and Oil Pastels
$3.74
Wen Zhengming Small Regular Script Love Lotus Essay Brush Tracing Practice Copybook Calligraphy Paper Copying Custom Wholesale for Beginners
$8.80
Heavy-duty Industrial Scouring Pad Roll with Aluminum Oxide for Stainless Steel Polishing and Rust Removal
$57.52
1.06m Leather Slitting Machine – Wide-Range Strip Cutter for Leather, Luggage, and Rubber Materials
$16,250.00
Ceramic Double-Boiler Steaming Bowl with Lid – Ideal for Eggs, Bird's Nest, Custard, and Soup for Home or Commercial Use
$21.11
![[Ya Que You Sheng] DT900 PRO X Calibration File V2 Version EQ Equalization](https://www.gosteppe.com/cache/small/product/269040/legacy-main-a3c0c55ffaafe89c05afced1.webp)
[Ya Que You Sheng] DT900 PRO X Calibration File V2 Version EQ Equalization
$15.00
![[Youxin Electronics] GP2Y0E03 Infrared Distance Sensor Module 4-50cm Range](https://www.gosteppe.com/cache/medium/product/74667/legacy-main-4da8cadc5fc82afe91b124e3.webp)
![[Trial Pack] Xianlang Complete Cat Treat Sticks Meal Packs Main Course Cans Freeze-Dried Cat Food Sample Snacks Gift Set](https://www.gosteppe.com/cache/medium/product/208273/legacy-main-9ec245ebf781f65a434ba854.webp)
