To fix the backlight color, press the "2" button. To turn off the backlight, press the "2" button again. Battery backed-up, DS1307 RTC (real time clock) will stay right on time, set the time once and forget it. If you have any questions happy to answer. All you need to do is solder all parts and you get a clock such as in the photo.
The item "Nixie Tube clock KIT with IN-18 Tube LED RGB Backlight Black PCB" is in sale since Friday, August 28, 2020. This item is in the category "Consumer Electronics\Vintage Electronics\Vintage Audio & Video\Vintage Parts & Accessories\Vintage Tubes & Tube Sockets". The seller is "trcorp" and is located in Rivne, Europe. This item can be shipped worldwide.