Opalescence Quick PF 45% Office Whitener, Refill: 4 - 1.2 ml Syringes with Tips. 45% carbamide peroxide gel. Results after 30 minutes of treatment. No gingival protection required. Contains PF (potassium nitrate and fluoride). Formulated to prevent dehydration and shade relapse. 4 - 1.2 ml syringes & tips