The T6613 is a small, compact CO2 module designed for integration into OEM equipment and existing control systems, featuring non-dispersive infrared (NDIR) detection with gold-plated optics and diffusion sampling. The module measures CO2 concentration from 0 to 2000 ppm with accuracy of ±30 ppm or 3% of reading (400–1250 ppm range) and ±5% of reading plus 30 ppm (1250–2000 ppm range), incorporating Telaire's patented ABC Logic self-calibration algorithm that eliminates the need for recalibration in most applications. It provides multiple output interfaces including UART at 19200 baud, I²C up to 100 kHz, and analog output (0–4 VDC), with a response time under 2 minutes and signal updates every 4 seconds. The module operates on 5 VDC regulated power with average consumption of 0.165 watts and is housed in compact dimensions of 57.15 mm × 34.67 mm × 15.24 mm. Ideal for HVAC systems, indoor air quality monitoring, and building automation applications where reliable, maintenance-free CO2 sensing is required.