The GT623 Series front mount closed circuit low profile sight gauges are molded from a clear nylon providing 180° of viewing. Integral to the sight gauge is a thermometer contained within a white colored card for direct reading of the fluid temperature. The white colored card helps draw eye contact to the fluid level quickly. Standard Features: 5 inch centerline length Front mount Tough, break resistant, transparent molded nylon gauge body 1.12 x .59 inch gauge body profile 180° of viewing fluid level (without metal guard) Viewing enhanced by white background integral to molded gauge body Card thermometer, dual scale 0°F to 220°F and -20°C to 110°C 1/2-13UNC threaded mounting bolts accommodate reservoir wall thicknesses up to .60 inches Suitable for use with most hydraulic and machine lubricating oils Temperature & Pressure Ratings: 212°F (100°C) maximum operating temperature 50 psi (345 kPa) maximum operating pressure at 70°F (21°C) Caution: Not recommended for use with alcohol or steam