Do I apply Extra Gloss Protection over Ultra Deep Shine?
No, Ultra Deep Shine is a stand-alone product and the use of Extra Gloss Protection or High Definition Wax is not recommended.

How often can Ultra Deep Shine be used without damaging paintwork?
Ultra Deep Shine will not damage the paintwork of your car.  It can be reapplied when the surface ceases to repel water, or an enhancement to the shine is required.