diff --git a/downloader/downloader.py b/downloader/downloader.py
index 4f631d9..c46403d 100644
--- a/downloader/downloader.py
+++ b/downloader/downloader.py
@@ -10,16 +10,15 @@
 
 # import third-party libraries
 import requests
+# import my libraries
+from exceptions import (BinacneBulkDownloaderDownloadError,
+                        BinanceBulkDownloaderParamsError)
 from rich import print
 from rich.progress import track
 
-# import my libraries
-from .exceptions import (BinacneBulkDownloaderDownloadError,
-                         BinanceBulkDownloaderParamsError)
-
 
 class BinanceBulkDownloader:
-    _CHUNK_SIZE = 10
+    _CHUNK_SIZE = 100
     _BINANCE_DATA_S3_BUCKET_URL = (
         "https://s3-ap-northeast-1.amazonaws.com/data.binance.vision"
     )
@@ -127,6 +126,8 @@ def __init__(
         self._data_frequency = data_frequency
         self._asset = asset
         self._timeperiod_per_file = timeperiod_per_file
+        self.marker = None
+        self.is_truncated = True
 
     def _check_params(self) -> None:
         """
@@ -171,20 +172,15 @@ def _check_params(self) -> None:
                     f"data_frequency 1s is not supported for {self._asset}."
                 )
 
-    def _get_file_list_from_s3_bucket(
-        self, prefix, marker=None, print_info=True, accumulated_length=0
-    ) -> list:
+    def _get_file_list_from_s3_bucket(self, prefix, marker=None, is_truncated=False):
         """
-        Get files from s3 bucket
+        Get file list from s3 bucket
         :param prefix: s3 bucket prefix
         :param marker: marker
-        :param print_info: print info
-        :param accumulated_length: accumulated length from previous recursive calls
+        :param is_truncated: is truncated
         :return: list of files
         """
-        if print_info:
-            print(f"[bold blue]Getting file list[/bold blue]: " + prefix)
-        files = []
+        print(f"[bold blue]Get file list[/bold blue]: " + prefix)
         params = {"prefix": prefix, "max-keys": 1000}
         if marker:
             params["marker"] = marker
@@ -192,28 +188,19 @@ def _get_file_list_from_s3_bucket(
         response = requests.get(self._BINANCE_DATA_S3_BUCKET_URL, params=params)
         tree = ElementTree.fromstring(response.content)
 
+        files = []
         for content in tree.findall(
             "{http://s3.amazonaws.com/doc/2006-03-01/}Contents"
         ):
             key = content.find("{http://s3.amazonaws.com/doc/2006-03-01/}Key").text
-            files.append(key)
+            if key.endswith(".zip"):
+                files.append(key)
+                self.marker = key
 
-        accumulated_length += len(files)
-        print(f"[green]Found {accumulated_length} files[/green]")
-        # Check if there are more files to retrieve
-        is_truncated = tree.find(
+        is_truncated_element = tree.find(
             "{http://s3.amazonaws.com/doc/2006-03-01/}IsTruncated"
-        ).text
-        if is_truncated == "true":
-            last_key = files[-1]
-            files.extend(
-                self._get_file_list_from_s3_bucket(
-                    prefix,
-                    marker=last_key,
-                    print_info=False,
-                    accumulated_length=accumulated_length,
-                )
-            )
+        )
+        self.is_truncated = is_truncated_element.text == "true"
 
         return files
 
@@ -319,21 +306,26 @@ def make_chunks(lst, n) -> list:
         """
         return [lst[i : i + n] for i in range(0, len(lst), n)]
 
-    def run_download(self) -> None:
+    def run_download(self):
         """
-        Execute download concurrently
+        Download concurrently
         :return: None
         """
         print(f"[bold blue]Downloading {self._data_type}[/bold blue]")
-        zip_files = [
-            prefix
-            for prefix in self._get_file_list_from_s3_bucket(self._build_prefix())
-            if prefix.endswith(".zip")
-        ]
-        # TODO: Filters by data_frequency if needed
-        for prefix_chunk in track(
-            self.make_chunks(zip_files, self._CHUNK_SIZE),
-            description="Downloading",
-        ):
-            with ThreadPoolExecutor() as executor:
-                executor.map(self._download, prefix_chunk)
+
+        while self.is_truncated:
+            file_list_generator = self._get_file_list_from_s3_bucket(
+                self._build_prefix(), self.marker, self.is_truncated
+            )
+            if self._data_type in self._DATA_FREQUENCY_REQUIRED_BY_DATA_TYPE:
+                file_list_generator = [
+                    prefix
+                    for prefix in file_list_generator
+                    if prefix.count(self._data_frequency) == 2
+                ]
+            for prefix_chunk in track(
+                self.make_chunks(file_list_generator, self._CHUNK_SIZE),
+                description="Downloading",
+            ):
+                with ThreadPoolExecutor() as executor:
+                    executor.map(self._download, prefix_chunk)