const string blobA = @"Publico8BEF883850D70BDB2729D174CC6B3DB0blob";
        const string blobB = @"Publico34C99D38A49BD6895156287980C6A4AFblob";
        const string blobC = @"Publico2914FDF6E301A0F76DB8DE4CEEE31E9Fblob";
        const string caminhoDestino = @"C:devarquivoTeste.webm";

        byte[] fileA = File.ReadAllBytes(blobA);
        byte[] fileB = File.ReadAllBytes(blobB);
        byte[] fileC = File.ReadAllBytes(blobC);

        List<byte> fileComplete = new List<byte>();
        fileComplete.AddRange(fileA);
        fileComplete.AddRange(fileB);
        fileComplete.AddRange(fileC);

        File.WriteAllBytes(path, fileComplete.ToArray());