The o-day Javelin is 14' 0" and is in it's own class. If your boat is 16'9" it is a Daysailer, and could either be a DS I, II, or III.
Does your boat look like the boat on this site?
http://www.sailboatowners.com/boats/spe ... 7307&bts=TIf so, it is a Javelin.
Now check the boats on this site.
http://www.sailboatowners.com/boats/mod ... o=60&bts=TThese are Daysailers. Essentially, the easy way to tell the difference between the DS I is that there is no built in hull liner, and has a lazerette deck. The DS II Has a molded in liner and a slightly narrower cuddy opening, and no lazerette deck. The DS III has a significantly smaller cuddy opening, and a higher deck near the transom. There is a good picture of a DS III on this site
http://www.boatshow.com/DaySailer.htmlCut and paste each of the above URL's into your browser and see which of these boats is most like yours. Failing identification through that method, get the serial number and post it here to confirm what you have including manufacture year.
Hope this helps.