---
product_id: 14520212
title: "55900 Intellasense II Refrigerant Leak Detector – Heated Tin Oxide Sensor, Super Sensitive Mode, Certified for R134a and R1234yf, Compact Design with LED Display and Leak Vial"
brand: "mastercool"
price: "$412.39"
currency: USD
in_stock: true
reviews_count: 7
url: https://www.desertcart.us/products/14520212-55900-intellasense-ii-refrigerant-leak-detector-heated-tin-oxide-sensor
store_origin: US
region: United States of America
---

# 6-Level LED Display 15.5" Flexible Probe Heated Tin Oxide Sensor 55900 Intellasense II Refrigerant Leak Detector – Heated Tin Oxide Sensor, Super Sensitive Mode, Certified for R134a and R1234yf, Compact Design with LED Display and Leak Vial

**Brand:** mastercool
**Price:** $412.39
**Availability:** ✅ In Stock

## Summary

> 🔍 Detect leaks before they detect you — stay ahead with Mastercool 55900!

## Quick Answers

- **What is this?** 55900 Intellasense II Refrigerant Leak Detector – Heated Tin Oxide Sensor, Super Sensitive Mode, Certified for R134a and R1234yf, Compact Design with LED Display and Leak Vial by mastercool
- **How much does it cost?** $412.39 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.us](https://www.desertcart.us/products/14520212-55900-intellasense-ii-refrigerant-leak-detector-heated-tin-oxide-sensor)

## Best For

- mastercool enthusiasts

## Why This Product

- Trusted mastercool brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **User-Friendly LED & Controls:** Intuitive multi-color LED indicators and adjustable sensitivity levels for seamless operation.
- • **Smart Probe, Zero False Alarms:** 15.5" flexible probe with environment-sensing tip minimizes false positives in complex settings.
- • **Certified for Industry Standards:** Meets SAE J2791, J2913, and EN 14624 certifications—trusted by pros worldwide.
- • **Peak Hold for Multi-Leak Mastery:** Locks highest leak signal while scanning continuously—never miss a critical detection.
- • **Pinpoint Precision, Fast Response:** Detects leaks as small as 0.15 oz/year with <1 second response time for ultimate accuracy.

## Overview

The Mastercool 55900 Intellasense II is a professional-grade refrigerant leak detector featuring a heated tin oxide sensor for ultra-sensitive detection of all common refrigerants including R134a and R1234yf. Certified to SAE and EN standards, it offers a 15.5" flexible probe with an intelligent tip to reduce false alarms, a peak hold function for multi-leak environments, and a user-friendly LED display. Compact and battery-powered, it delivers fast, reliable leak detection with up to 30 hours of battery life, making it an essential tool for HVAC and automotive professionals.

## Description

Mastercool 55900 Intellasense II Refrigerant Leak Detector – Heated Tin Oxide Sensor, Super Sensitive Mode, Certified for R134a and R1234yf, Compact Design with LED Display and Leak Vial

## Features

- ✔️ HEATED TIN OXIDE SENSOR – Detects all refrigerants (CFCs, HCFCs, HFCs, and blends) with high sensitivity and fast response time
- ✔️ CERTIFIED PERFORMANCE – Complies with SAE J2791 (R134a), J2913 (R1234yf), and EN 14624 standards
- ✔️ SUPER SENSITIVE MODE – Enables enhanced detection of small leaks, including R1234yf and R407C
- ✔️ INTELLIGENT PROBE DESIGN – 15.5” flexible probe with environment-sensing tip minimizes false alarms
- ✔️ PEAK HOLD FUNCTION – Locks the highest leak signal while continuing to scan for additional leaks
- ✔️ USER-FRIENDLY INTERFACE – Volume/mute control, three sensitivity levels, and LED indicators for signal strength, sensor status, and diagnostics
- ✔️ INCLUDES ACCESSORIES – Comes in a blow molded case with leak test vial, replacement filters, and 2 “C” batteries
- ✔️ U.S. BASED CUSTOMER SUPPORT – Reliable service from Mastercool’s New Jersey headquarters

## Technical Specifications

| Specification | Value |
|---------------|-------|
| Brand | Mastercool |
| Style | Intellasense II – Heated Tin Oxide Sensor |
| Power Source | Battery Powered |
| Color | Blue |
| Product Dimensions | 30"D x 8"W x 6"H |
| Item Weight | 1 Pounds |
| Alarm | Vibration |
| Global Trade Identification Number | 00700376559002 |
| Number of Items | 1 |
| Manufacturer | Mastercool |
| UPC | 700376559002 |
| Model | 55900 |
| Item Weight | 1 pounds |
| Item model number | 55900 |
| Batteries | 2 C batteries required. (included) |
| Is Discontinued By Manufacturer | No |
| Manufacturer Part Number | 55900 |

## Product Details

- **Brand:** Mastercool
- **Style:** Intellasense II – Heated Tin Oxide Sensor
- **Power Source:** Battery Powered
- **Color:** Blue
- **Product Dimensions:** 30"D x 8"W x 6"H
- **Item Weight:** 1 Pounds
- **Alarm:** Vibration
- **Global Trade Identification Number:** 00700376559002
- **Number of Items:** 1
- **Manufacturer:** Mastercool

## Images

![55900 Intellasense II Refrigerant Leak Detector – Heated Tin Oxide Sensor, Super Sensitive Mode, Certified for R134a and R1234yf, Compact Design with LED Display and Leak Vial - Image 1](https://m.media-amazon.com/images/I/51LbVxWwkeL.jpg)

## Available Options

This product comes in different **Style** options.

## Customer Reviews

### ⭐⭐⭐⭐⭐ Best investment
*by A***C on February 27, 2025*

Great product,does its job flawlessly

### ⭐⭐⭐⭐ Professional grade refrigerant detector
*by D***K on March 16, 2021*

I used to use a Harbor Freight detector before this for R-134a vehicle applications. Those inexpensive detectors from HF, and other imports here on Amazon can work to a degree, but when it came time for a replacement I did the research and selected this Mastercool 55900. The 55900 has proven to be superior overall to the more entry level tools.User interface wise you can both control the volume and mute the tones. The self test LEDs, sensitivity LEDs, and detection LEDs are all green in color and of high brightness so you can easily see them in sunlight. You can control the degree of sensor sensitivity via the touch pad controls as well.Features wise the tool comes in a rugged shop grade storage case, and includes two Energizer C batteries (I recommend you always store the tool with the batteries removed to prevent damage to the tool from them leaking if you are not using the tool regularly). Easy to read and understand instructions are included in hard copy, as well as via a PDF on the Mastercool website. Mastercool includes a small glass vial of a test gas that you can use to check that the tool remains functional and in calibration. A very professional and high quality touch.However, I only gave this tool 4 starts out of 5 because I found it often required multiple passes to confirm the location of very small R-134a leaks, and with the sensor housing in nearly direct contact to the hose or pipe itself. These are leaks I would not expect lower cost tools to detect at all, and so the rating is less a reflection on the 55900 and more on the abilities of electronic detectors in general. I only use them as a last resort when R-134a dye injection is not an option.

### ⭐⭐⭐ The box arrived broken
*by X***Z on December 30, 2024*

The box arrived broken

## Frequently Bought Together

- Mastercool Refrigerant Leak Detector with Metal Oxide Gas Sensor, IntellaSense II, 55900, Blue
- Mastercool 53123-YF Refillable R1234yf Oil/Dye Injector

---

## Why Shop on Desertcart?

- 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016
- 🌍 **Shop Globally** — Access 737+ million products across 21 categories
- 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price
- 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members)
- 🔒 **Secure Payments** — Trusted payment options with buyer protection
- ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews

**Shop now:** [https://www.desertcart.us/products/14520212-55900-intellasense-ii-refrigerant-leak-detector-heated-tin-oxide-sensor](https://www.desertcart.us/products/14520212-55900-intellasense-ii-refrigerant-leak-detector-heated-tin-oxide-sensor)

---

*Product available on Desertcart United States of America*
*Store origin: US*
*Last updated: 2026-02-18*