diff --git a/src/Data/Bits/ToolsYj.hs b/src/Data/Bits/ToolsYj.hs
--- a/src/Data/Bits/ToolsYj.hs
+++ b/src/Data/Bits/ToolsYj.hs
@@ -1,8 +1,12 @@
 {-# OPTIONS_GHC -Wall -fno-warn-tabs #-}
 
-module Data.Bits.ToolsYj (checkBits) where
+module Data.Bits.ToolsYj (checkBits, bitsList) where
 
 import Data.Bits
 
 checkBits :: Bits bs => bs -> bs -> Bool
 checkBits wnt = (== wnt) . (.&. wnt)
+
+bitsList :: FiniteBits bs => bs -> [bs]
+bitsList bs =
+	filter (/= zeroBits) $ map ((bs .&.) . bit) [0 .. finiteBitSize bs - 1]
diff --git a/tools-yj.cabal b/tools-yj.cabal
--- a/tools-yj.cabal
+++ b/tools-yj.cabal
@@ -5,7 +5,7 @@
 -- see: https://github.com/sol/hpack
 
 name:           tools-yj
-version:        0.1.0.19
+version:        0.1.0.20
 synopsis:       Tribial tools
 description:    Please see the README on GitHub at <https://github.com/YoshikuniJujo/tools-yj#readme>
 category:       Tools