Items in set
The number of main items in the set (see "Product Type"). The main items are actually pencils or crayons; accessories like sharpeners, caps, etc. are not taken into account here.
In the case with pencils, the minimum number of items in a set is 2, while the maximum varies depending on the purpose of use (see below). Sets of graphite pencils of more than 20 units already belong to the premium class, in colour there are options for several dozen, and in watercolor sets (see "Watercolor pencils") the number of shades can exceed 120. In all cases, the more pencils in the set — the wider your options for choosing the currently required one. However, the cost of the set increases accordingly.
By default, crayon sets are only coloured, there are usually at least 6 items in a set.
Lead Diameter
The thickness of the lead (writing rod) in a pencil or each crayon in a set (see "Product Type").
The meaning of this parameter depends on the specs of the pencil. So, in traditional pencils (lead in the casing), the thickness of the lead determines only the maximum thickness of the line that can be drawn in one pass. In collet models (see above), this parameter is also necessary to search for refill leads: their diameter must correspond to the size of the lead slot of the collet. And interchangeable leads with a diameter of more than 2 mm, usually, also have to be sharpened. However, anyway, each size is good for its tasks: thin leads are convenient for precise small work, and for large volumes of shading, it is desirable to have thicker pencils — they are not only more convenient, but also do not expend so fast.
As for the crayons, their thickness primarily determines the ease of use, as well as compatibility with special collet pencils that play the role of holders.
