You can call them bridges, bridge connectors, or strap connectors. Call them whatever you like, but at Emmaline Bags, they call them Strap Keepers because they like to keep your strap in line! These are gorgeous, and high quality. With the 1/4″ (6mm) height, you should be able to get 1 or 2 layers of strap underneath, depending on how you are using them.
1″ Wide strap opening
25 mm (1″) wide x 6 mm (1/4″) high
Available in packs of 2