diff --git a/src/cryptocom/exchange/helpers.py b/src/cryptocom/exchange/helpers.py
index 84101c2..6eebf51 100644
--- a/src/cryptocom/exchange/helpers.py
+++ b/src/cryptocom/exchange/helpers.py
@@ -1,4 +1,7 @@
-def round_up(value: str, precision: int) -> float:
+import typing as TP
+
+
+def round_up(value: TP.Union[float, str], precision: int) -> float:
     """Rounds number to upper precision 0.13 -> 0.2"""
     pwr = 10**precision
     value = float(value)
@@ -8,7 +11,7 @@ def round_up(value: str, precision: int) -> float:
     return rounded
 
 
-def round_down(value: str, precision: int) -> float:
+def round_down(value: TP.Union[float, str], precision: int) -> float:
     """Rounds number to lower precision 0.13 -> 0.1"""
     value = float(value)
     pwr = 10**precision
diff --git a/src/cryptocom/exchange/structs.py b/src/cryptocom/exchange/structs.py
index 9e2b314..a50ecb6 100644
--- a/src/cryptocom/exchange/structs.py
+++ b/src/cryptocom/exchange/structs.py
@@ -1,4 +1,5 @@
 import time
+import typing as TP
 from dataclasses import dataclass
 from datetime import datetime
 from enum import Enum, IntEnum
@@ -62,8 +63,8 @@ class DefaultPairDict(dict):
 @dataclass
 class MarketTicker:
     pair: Pair
-    buy_price: float | None
-    sell_price: float | None
+    buy_price: TP.Union[float, None]
+    sell_price: TP.Union[float, None]
     trade_price: float
     time: int
     volume: float