diff --git a/src/cryptography/hazmat/primitives/keywrap.py b/src/cryptography/hazmat/primitives/keywrap.py
index 89925f3..6e79ab6 100644
--- a/src/cryptography/hazmat/primitives/keywrap.py
+++ b/src/cryptography/hazmat/primitives/keywrap.py
@@ -29,8 +29,9 @@
     n = len(r)
     for j in range(6):
         for i in range(n):
-            # every encryption operation is a discrete 16 byte chunk so
-            # it is safe to reuse the encryptor for the entire operation
+            # every encryption operation is a discrete 16 byte chunk (because
+            # AES has a 128-bit block size) and since we're using ECB it is
+            # safe to reuse the encryptor for the entire operation
             b = encryptor.update(a + r[i])
             # pack/unpack are safe as these are always 64-bit chunks
             a = struct.pack(