I need to use Ext.slider.Slider for the events not provided in Ext.field.Slider (e.g. dragstart, dragend), and I noticed that Ext.slider.Slider wasn't available in the toolbox, only a Ext.field.Slider. For whatever it's worth I thought it odd that:
the 'dragstart' and 'dragend' events weren't available in the sliderfield
that the distinction between slider and slider field existed (although, I'm sure there's a good reason)
since there is a distinction and they have different events, both items weren't accessible in toolbox.