Slider Controls - Toggles the display of Sliders. Sliders are not available for all radios. They are used for adjustments to various operating parameters such as audio gain, RF Gain, Filters, etc. If your radio does not provide the facility, they will not be available in the program. The FT-847, for example, does not have them. I guess it just depends on how many facilities are digitally controlled or enabled in the particular rig.A right click on a slider provides a coarse choice of three positions - Minimum, Centre and Maximum.
The image shown here relates to the Ten-Tec Orion ®Dem-o-Matic® screen. I had to get a slider view somehow.
If sliders are available for your particular radio, you can set up your own layout in the Tools, Program Options, Sliders Layout menu selection. There is a default and up to 5 alternative layouts available.