For older versions of the GT500 User Guide, click here
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Free GT500 "Firmware Update Utility" PC Software
The free Microsoft Windows application (not required for operation) is compatible with any version of Windows from WinXP through Win10. The Utility enables fast and reliable upgrading of
the GT500 firmware when the PC is connected to the charger via its embedded USB interface (no dongles required). With embedded USB support, connecting to a PC for this purpose has never
Compatible Parallel Adapters
GT Series Supports the Revolectrix SPA and MPA Safe Parallel Adapters. Look for the MPA Combo in the online stores! For more information about these unique Safe Parallel Adapters, see
"Native XH Adapters" at the above link (bottom of the page).