No you don’t . . .
Over the years it has become apparent to us that some photographers are concerned about/reluctant to use self adhesive VELCRO® Brand on their flash units. As a result we added the UltraStrap, the strongest product of it's kind on the market. UltraStrap's unique patent-pending design features loops that stretch and apply even pressure to hold it firmly in place on the flash head. Allowing all your VELCRO® accesories to attach to your flash head while still retaining the same strength as VELCRO® adhesive.
So, when you are ready to remove the UltraStrap, it leaves no adhesive residue on the flash.
While the UltraStrap is a very reasonable option, we’d like to offer the following regarding attachment alternatives:
We offer this information not to imply that there are bad decisions, only options...an informed decision is a better decision