diff --git a/proxy_scraper_checker/output.py b/proxy_scraper_checker/output.py
index fcf286c..5f05004 100644
--- a/proxy_scraper_checker/output.py
+++ b/proxy_scraper_checker/output.py
@@ -80,9 +80,9 @@ async def save_proxies(*, settings: Settings, storage: ProxyStorage) -> None:
             if mmdb is not None:
                 await asyncio.to_thread(mmdb.close)
     if settings.output_txt:
-        sorted_proxies = sorted(storage, key=settings.sorting_key)
+        sorted_proxies = sorted(storage, key=settings.get_sorting_key())
         grouped_proxies = tuple(
-            (k, sorted(v, key=settings.sorting_key))
+            (k, sorted(v, key=settings.get_sorting_key()))
             for k, v in storage.get_grouped().items()
         )
         for folder, anonymous_only in (
diff --git a/proxy_scraper_checker/proxy.py b/proxy_scraper_checker/proxy.py
index 064201c..b60ed87 100644
--- a/proxy_scraper_checker/proxy.py
+++ b/proxy_scraper_checker/proxy.py
@@ -42,7 +42,6 @@ class Proxy:
     timeout: float | None = attrs.field(default=None, init=False, eq=False)
     exit_ip: str | None = attrs.field(default=None, init=False, eq=False)
 
-    @property
     def is_checked(self) -> bool:
         return self.timeout is not None
 
diff --git a/proxy_scraper_checker/settings.py b/proxy_scraper_checker/settings.py
index d663c7d..57e4049 100644
--- a/proxy_scraper_checker/settings.py
+++ b/proxy_scraper_checker/settings.py
@@ -231,8 +231,7 @@ class Settings:
     )
     timeout: ClientTimeout = attrs.field(converter=_timeout_converter)
 
-    @property
-    def sorting_key(
+    def get_sorting_key(
         self,
     ) -> Callable[[Proxy], float] | Callable[[Proxy], tuple[int, ...]]:
         return (
diff --git a/proxy_scraper_checker/storage.py b/proxy_scraper_checker/storage.py
index 30f4c24..01e801a 100644
--- a/proxy_scraper_checker/storage.py
+++ b/proxy_scraper_checker/storage.py
@@ -56,7 +56,7 @@ class ProxyStorage:
 
     def remove_unchecked(self) -> None:
         for p in self._proxies.copy():
-            if not p.is_checked:
+            if not p.is_checked():
                 self._proxies.remove(p)
 
     def __iter__(self) -> Iterator[Proxy]: