The sleeve with The SureCure Windowâ„¢ is proven to produce cured restorations equal to those where no barrier is used. Unique individually wrapped, easy-peel outer wrapping protects inner sleeve from contamination and eliminates the potential for bacteria build-up on curing light surfaces.- Curing Light Sleeve, Custom Fit For Kerr Demi Ultra, 100/bx, 5 bx/cs Stock Item