Selecting a glass dome is a good choice, for the elegant look of your display.  Glass domes come in 2 pieces (Glass dome and a wooden base), with the glass dome lifting off the base.

When deciding how wide of a dome (inside) you need, always use the 2 inch rule. 

 Measure the total width of the item you wish to display, then add 2 inches. This would be the "diameter" of the base you would need.  It will give your display item 1 inch on either side, to prevents a "cramped" look, and makes a nicer viewing display piece. Most bases are wider then then diameter listed, with usually a 1" lip beyond the "groove" in the base. This width does get smaller, the smaller dome your purchase.

When deciding how tall you need your dome to be, again, use the 2 inch rule.  Measure the total height of your display object, and add 2 inches. Domes curve on the top, and this will help prevent your object top from getting placed in the curving area. You may have to go above the 2" rule on top, to find a height you need. Or just email me, I love to help!

When placing items on ebay, my domes are described by the inside area.

Domes come with a choice of real wooden bases ( Walnut, Oak ) or more shiny surfaces (Satin, Brass, Shiny Brass) Check the description of each dome, to see your choices.  Most have a pick of several choices, blending in with your home decor.  Bases come with felt or rubber tabs under the base, to keep it from sliding or scratching the surface you set it on, to display.

If still not sure, email me, I love to help my customers find the correct combination, to display their collectables with a smile!