When downloading a rar file from the internet with the code below, the downloaded file is larger than it actually is. Not sure what causes this?

        bis = new BufferedInputStream(urlConn.getInputStream());
        bos = new BufferedOutputStream(new FileOutputStream(outputFile));

        eventBus.fireEvent(this, new DownloadStartedEvent(item));

        int read;
        byte[] buffer = new byte[2048];
        while ((read = bis.read(buffer)) != -1) {
            bos.write(buffer);
        }

        eventBus.fireEvent(this, new DownloadCompletedEvent(item));