Read above link for customization.
Material: Stainless Steel/Titanium
The below 3 sizes is must needed:
1.Chastity Cage Overall Length
2.Penis Tube Inner Diameter
3.Base Ring Inner Diameter
For other sizes,such as the horizontal gap between base ring and penis tube,it is around 10mm by default,but it is customizable too,so if you have demand on this size,you can specify this size in the corresponding text box.
For more style details,such as adding scrotum bar,PA hook,.etc.you can specify your demands in the corresponding text box.
If you think the text cannot accurately describe your needs, you can draw and upload pictures to make your customization more precise.
Warm tip: if you are not very sure about the base ring diameter or want to try one more size of base ring,you can choose "cage with 2 base ring" to place the order.