diff --git a/rainbowadn/instrument/instrumentation.py b/rainbowadn/instrument/instrumentation.py
index fe65171..6bf3ba8 100644
--- a/rainbowadn/instrument/instrumentation.py
+++ b/rainbowadn/instrument/instrumentation.py
@@ -1,13 +1,13 @@
 import functools
 from contextlib import ExitStack
-from typing import Callable, Generic, TypeVar
+from typing import Callable, TypeVar
 
 __all__ = ('Instrumentation',)
 
-IType = TypeVar('IType')
+IType = TypeVar('IType', bound='Instrumentation')
 
 
-class Instrumentation(Generic[IType]):
+class Instrumentation:
     deinstrumentation = {}
     _method: Callable
     _wrap: Callable
@@ -24,8 +24,6 @@ class Instrumentation(Generic[IType]):
         raise NotImplementedError
 
     def __enter__(self: IType) -> IType:
-        if not isinstance(self, Instrumentation):
-            raise TypeError
         if hasattr(self, '_method') or hasattr(self, '_wrap'):
             raise RuntimeError
         method = getattr(self.target, self.methodname)