Those are actually my shoes. With the crown, you really are going to need to use ribbon to attach the buckle to the strap. If you don't, the bars will show.
Some of my other buckles (www.thebuckleboutique.com
) work well without any ribbon, but the crown is not one that I recommend doing without it.
Some of my buckles that work well on flip flops without ribbon include: the fleur de lis, puffy heart, kitty, skull and cross bone, the solid peace signs, flower, all the sports: baseball, softball, football, soccer, basketball, volleyball, tennis ball, etc.
I suggest you rough up the surface of the buckle and flip flop strap. Then take fishing line or microfilament and very tightly wrap it around the buckle's bar and the flip flop strap. Once the buckle is securely fastened to the strap, squeeze some E-6000 between the buckle and the strap. Clamp the buckle to the strap until the E-6000 is completely dry. Wha! La! You have just embellished your flip flop!
Another option that I have just introduced is the shoe clip. Those are super easy (and come in the crown) is the clip. You just sell the clip and the customer puts it on themselves. It requires no work on your part and you can offer your customer more choices and opportunities to purchase more!
Please let me know if I can answer any other questions.