diff --git a/tests/unit/test_model_configurations.py b/tests/unit/test_model_configurations.py
new file mode 100644
index 000000000..2337d40be
--- /dev/null
+++ b/tests/unit/test_model_configurations.py
@@ -0,0 +1,25 @@
+from functools import lru_cache
+
+import pytest
+
+from transformer_lens import loading
+from transformer_lens.HookedTransformerConfig import HookedTransformerConfig
+
+
+@lru_cache(maxsize=None)
+def get_cached_config(model_name: str) -> HookedTransformerConfig:
+    """Retrieve the configuration of a pretrained model.
+
+    Args:
+        model_name (str): Name of the pretrained model.
+
+    Returns:
+        HookedTransformerConfig: Configuration of the pretrained model.
+    """
+    return loading.get_pretrained_model_config(model_name)
+
+
+@pytest.mark.parametrize("model_name", loading.DEFAULT_MODEL_ALIASES)
+def test_model_configurations(model_name: str):
+    """Tests that all of the model configurations are in fact loaded (e.g. are not None)."""
+    assert get_cached_config(model_name) is not None, f"Configuration for {model_name} is None"
diff --git a/transformer_lens/HookedTransformerConfig.py b/transformer_lens/HookedTransformerConfig.py
index 4458705de..ec48eb185 100644
--- a/transformer_lens/HookedTransformerConfig.py
+++ b/transformer_lens/HookedTransformerConfig.py
@@ -245,7 +245,7 @@ class HookedTransformerConfig:
     tokenizer_prepends_bos: Optional[bool] = None
     n_key_value_heads: Optional[int] = None
     post_embedding_ln: bool = False
-    rotary_base: int = 10000
+    rotary_base: float = 10000.0
     trust_remote_code: bool = False
     rotary_adjacent_pairs: bool = False
     load_in_4bit: bool = False
diff --git a/transformer_lens/components/abstract_attention.py b/transformer_lens/components/abstract_attention.py
index 347548f34..6311aa2e4 100644
--- a/transformer_lens/components/abstract_attention.py
+++ b/transformer_lens/components/abstract_attention.py
@@ -469,7 +469,7 @@ def calculate_sin_cos_rotary(
         self,
         rotary_dim: int,
         n_ctx: int,
-        base: int = 10000,
+        base: float = 10000,
         dtype: torch.dtype = torch.float32,
     ) -> Tuple[Float[torch.Tensor, "n_ctx rotary_dim"], Float[torch.Tensor, "n_ctx rotary_dim"]]:
         """
diff --git a/transformer_lens/loading_from_pretrained.py b/transformer_lens/loading_from_pretrained.py
index aa544786f..2e929a810 100644
--- a/transformer_lens/loading_from_pretrained.py
+++ b/transformer_lens/loading_from_pretrained.py
@@ -777,7 +777,7 @@ def convert_hf_model_config(model_name: str, **kwargs):
             "rotary_dim": 4096 // 32,
             "final_rms": True,
             "gated_mlp": True,
-            "rotary_base": 1000000,
+            "rotary_base": 1000000.0,
         }
         if "python" in official_model_name.lower():
             # The vocab size of python version of CodeLlama-7b is 32000