The primary difference between a New Design and an Old Design version for the Feather (XL) is the pendant hole.
While the pendant hole with New Design has a rounded shape, the Old Design has a pointed shape.
As you may have realized already, the length of the Feather with New Design is longer than the Feather with Old Design.
Generally, the Old Design Feather (XL) is only suitable for Small Cornered Chains.
However, approximately 70% of them had been customized by widening the pendant hole.
This allows the Large Cornered and Large Round Chains to pass through.
(It is indicated on the item page whether the pendant hole has been modified or not.)
The Leather Cord is a better option for Old Design Feathers without any modification to the pendant hole.
This is because the Feather will be much secured, and the unnecessary gap between the Feather and the hole can be avoided.
Choose the Feather that you prefer!