diff --git a/lib/eth/abi/encoder.rb b/lib/eth/abi/encoder.rb
index f2ee06d8..ca3792d7 100644
--- a/lib/eth/abi/encoder.rb
+++ b/lib/eth/abi/encoder.rb
@@ -285,13 +285,9 @@ def address(arg)
       # The ABI encoder needs to be able to determine between a hex `"123"`
       # and a binary `"123"` string.
       def handle_hex_string(arg, type)
-        if Util.prefixed? arg or
-           (arg.size === type.sub_type.to_i * 2 and Util.hex? arg)
-
+        if (arg.size === type.sub_type.to_i * 2 and Util.hex? arg)
           # There is no way telling whether a string is hex or binary with certainty
-          # in Ruby. Therefore, we assume a `0x` prefix to indicate a hex string.
-          # Additionally, if the string size is exactly the double of the expected
-          # binary size, we can assume a hex value.
+          # in Ruby.
           Util.hex_to_bin arg
         else