I found this quote at the Mandarin Mansion site:
Its wide quillons make it even useful in Japanese sai-fighting systems, a weapon also known in China as an "iron ruler".
Now what is the relation of the sai, which I have found offered in this form:
http://www.chinese-weapon.com.tw/english-S204.htm
to the hard whip:
http://www.gungfu.com/htm-weapons/chine ... d-whip.htm
and another hard whip:
http://www.wle.com/products/W604-C.html
and here is one called hard club:
http://www.wle.com/products/WS106-C.html
In his book on Chinese weapons Yang Jwing-Ming states that this weapon was often just a piece of metal and came with and without a handle. Now in a few places there is the statement that the Iron Ruler is the same as the sai. I have also found the Hard Whip called "Bian", and this Bian looks close, but not the same as the weapon Tieh Chi:
http://www.sevenstarstrading.com/html/swords/1112.html
What is the relationship of these weapons, and how do they relate to the taiji ruler?
I have read about Yang Ban-Hou having skill with a weapon like these, is this accurate?