Brook One offers 4 different fire barrier products. Two Standard Products – burnthough cover films BO 856B-I & BO 856B-II, and two Lightweight Products – burnthough cover films BO 856B-I-LWT & BO 856B-II-LWT. These high performance cover films are used in the fabrication of thermal/acoustic aircraft insulation blankets with excellent properties: Strong, Flexible, Durable and Heat &Ultrasonic Sealable.