
1210K31 Comparison
| photo | price | summary | rating |
|---|---|---|---|
![]() | $36.99 | Top Pick! Condition is New, Sight Glass Excellent View Star Reflector For Maximum Visibility, 1" NPT-Male, shipping cost = $8.60 | 99.4% |
![]() | $45.02 | Condition is New, Sight Glass, Easy-to-See, WITH REFLECTOR, Maximum visibility, 1" NPT , # 1210K31, shipping cost = $8.60 | 99.4% |

Introducing the McMaster-Carr 1210K31 Sight Glass, a premium component designed to ensure maximum visibility into your fluid systems. This easy-to-install sight glass is engineered with a high-quality reflector that enhances light transmission, making it an ideal choice for applications where clear observation of fluid levels is essential.
Measuring 3 inches in diameter and 2 inches in height, this sight glass is compact yet effective. Its NPT (National Pipe Thread) connection makes it compatible with a wide range of industrial and commercial piping systems. The glass material is made of borosilicate, a type of glass renowned for its exceptional strength and durability, capable of withstanding temperature fluctuations and corrosive environments.
The McMaster-Carr 1210K31 Sight Glass features a unique design, with a reflector that is angled at 45 degrees to optimize light reflection and provide a clear view of the fluid levels even in poorly lit areas. This reflector is made of polished stainless steel, ensuring a long-lasting, corrosion-resistant component that complements your system's aesthetic.
Installation is straightforward. The sight glass comes with a gasket included, ensuring a secure seal and preventing leaks. The glass itself is protected by a stainless steel faceplate, shielding it from potential impacts and ensuring its longevity.
In summary, the McMaster-Carr 1210K31 Sight Glass is an excellent addition to any fluid handling system. Its maximum visibility reflector, durable borosilicate glass, and NPT connection make it a versatile and reliable component. With its compact design and easy installation, you can trust this sight glass to provide clear and accurate readings, helping you maintain optimal performance in your industrial or commercial applications.
McMaster-Carr 1210K31 Sight Glass: A Comprehensive Analysis
The McMaster-Carr 1210K31 Sight Glass is a product designed for maximum visibility in various applications. In this analysis, we will examine the key features, advantages, and disadvantages of this sight glass to help you make an informed decision.
Features:1. Easy-to-install design that can be used in both horizontal and vertical applications.
2. High-performance, die-cast aluminum body.
3. Tempered glass with a reflective coating for enhanced visibility.
4. NPT (National Pipe Thread) threading for easy connection to fluid lines.
5. Available in various sizes.
Advantages:1. Improved visibility: The reflective coating ensures clear viewing of the fluid level, even in low-light conditions.
2. Durable construction: The die-cast aluminum body is resistant to corrosion and offers excellent strength.
3. Versatile: This sight glass can be used in various industries, including chemical processing, food and beverage, and HVAC systems.
4. Easy installation: The NPT threading makes it simple to install, saving time and effort.
Disadvantages:1. Cost: The McMaster-Carr 1210K31 Sight Glass may be more expensive compared to other sight glasses without the reflective coating.
2. Limited temperature range: This sight glass is not suitable for high-temperature applications as the tempered glass may not withstand extreme temperatures.
Conclusion:The McMaster-Carr 1210K31 Sight Glass is an excellent investment for applications where maximum visibility is crucial. Its durable construction, easy installation, and versatility make it a valuable addition to various industries. However, its higher cost and limited temperature range may be a drawback for some users.
Recommendation:If you require a sight glass for applications with low-light conditions or where maximum visibility is essential, the McMaster-Carr 1210K31 Sight Glass is a recommended option. Its reflective coating ensures clear visibility, while its durable construction guarantees longevity. If cost is a concern or if high temperatures are present, it would be wise to consider alternative sight glass options.
Details:
Part# 1210K31. Most guys use the clear window for lighter colored fluids and reflector dark liquids. Seal is buns-n. Maximum visibility.
Sights for dark liquid have a reflector that makes easy to see, especially in low-light conditions. Brass sights are for use with hydraulic oil and water. Temperature range is -40 to 180. Clear window with reflector behind glass.
Pipe size: window diameter: brass with the reflector behind clear window. See inside tanks, gear cases, bearing housings, and mixers.
specifications maxohvac:
- brand: Mcmaster-carr
- mpn: 1210k31
- part type: Glass
- product type: Sight Glass
- country of manufacture: United States
shipping maxohvac:
- carrier: usps, ups
- transit: 4-8 days
- service: usps ground advantage, usps priority mail, usps priority mail express, ups ground saver
- class: standard, expedited, economy
- type: calculated
payments maxohvac:
- credit card: discover
- other
- wallet: apple-pay
returns maxohvac:
- policy: no returns
seller maxohvac:
- rating: 98.7%
- city: hartford, wisconsin
- # reviews: 147729
general maxohvac:
- category: Business & Industrial > Hvac Refrigeration
offer maxohvac:
- started: may 30, 2025
- in stock #: 2
- prices: $36.99–$45.02
- item condition: New
- availability: in stock
- sold #: 18
- options: ship-to-home

