The Experience Add On allows for a new entry on the radius selector on the user interface.   When a Radius First Entry has been set it will appear as the initial text in the radius drop down that the user sees on your search form.   The value will be set to the default miles that you have set in Radii Options.

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Setting Radius First Entry

Go to the Experience / Search tab in Store Locator Plus.   Look for Radius First Entry in the Search Labels section.

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Setting The Default Radius

The radius used when the first entry is selected is the default radius entered in radii options. Radii Options is a comma-separated list of numbers that are the different radius options the user can select from. The default is the number in parenthesis.

SLP 4.5 Experience Search Features Settings
SLP 4.5 Experience Search Features Settings