diff --git a/great_ai/utilities/parallel_map/parallel_map.py b/great_ai/utilities/parallel_map/parallel_map.py
index 4472642..a233e39 100644
--- a/great_ai/utilities/parallel_map/parallel_map.py
+++ b/great_ai/utilities/parallel_map/parallel_map.py
@@ -101,7 +101,7 @@ def parallel_map(
         input_values: An iterable of items that `func` is applied to.
         chunk_size: Tune the number of items processed in each step. Larger numbers
             result in smaller communication overhead but less parallelism at the start
-            and end. If `chunk_size` has a `__len__` property, the `chunk_size` is
+            and end. If `input_values` has a `__len__` method, the `chunk_size` is
             calculated automatically if not given.
         ignore_exceptions: Ignore chunks if `next()` raises an exception on
             `input_values`. And return `None` if `func` raised an exception in a worker
diff --git a/great_ai/utilities/parallel_map/simple_parallel_map.py b/great_ai/utilities/parallel_map/simple_parallel_map.py
index 7a506b3..036508a 100644
--- a/great_ai/utilities/parallel_map/simple_parallel_map.py
+++ b/great_ai/utilities/parallel_map/simple_parallel_map.py
@@ -32,7 +32,7 @@ def simple_parallel_map(
         input_values: An iterable of items that `func` is applied to.
         chunk_size: Tune the number of items processed in each step. Larger numbers
             result in smaller communication overhead but less parallelism at the start
-            and end. If `chunk_size` has a `__len__` property, the `chunk_size` is
+            and end. If `input_values` has a `__len__` method, the `chunk_size` is
             calculated automatically if not given.
         concurrency: Number of new processes to start. Shouldn't be too much more than
             the number of physical cores.
diff --git a/great_ai/utilities/parallel_map/threaded_parallel_map.py b/great_ai/utilities/parallel_map/threaded_parallel_map.py
index 7ad179f..151158e 100644
--- a/great_ai/utilities/parallel_map/threaded_parallel_map.py
+++ b/great_ai/utilities/parallel_map/threaded_parallel_map.py
@@ -99,7 +99,7 @@ def threaded_parallel_map(
         input_values: An iterable of items that `func` is applied to.
         chunk_size: Tune the number of items processed in each step. Larger numbers
             result in smaller communication overhead but less parallelism at the start
-            and end. If `chunk_size` has a `__len__` property, the `chunk_size` is
+            and end. If `input_values` has a `__len__` method, the `chunk_size` is
             calculated automatically if not given.
         ignore_exceptions: Ignore chunks if `next()` raises an exception on
             `input_values`. And return `None` if `func` raised an exception in a worker