Features 1. Two-parts dual mode of the main and auxiliary part facilitates the transmittance measurement of the automobile front windshield glass and building glass. 2. The built-in lithium rechargeable battery is easy for use without replacing the battery; 3. Use the USB port of computer to charge the meter via the built-in charger; 4. The laser alignment function guarantees the accurate alignment of the main part with the auxiliary part in the process of measurement and ensures accurate measurement. 5. Three light Transmittance Meter in one device; result is the average of three values 6. Two laser for two part alignment, more accuracy.