InStyler Original Rotating Hot Iron Brush Hair Styler 1.25" Barrel IS1001 Tested. The InStyler Original Rotating Hot Iron (Model IS1001/IS1001.1) is a 1.25-inch, silver-colored, 3-in-1 styling tool that straightens, curls, and adds volume. It uses a rotating ceramic barrel and ionic technology to smooth hair, with maximum temperatures around 410 to 450 degrees. This item is in excellent preowned condition.