A major misconception in the angling world is that a "Weight Forward" (WF) line is a "Weight Forward" line and a "Double Taper" line is a "Double Tape" line! Just as a "Double Taper" (DT) fly line is significantly different than a WF fly line, a brand "X" WF fly line can be significantly different than a brand "Y" WF fly line (and the same holds true for DT fly lines).

In addition to that fact that not all lines are accurately sized (refer to Tech Tip "Over/Under Lining"), the design of fly lines varies considerably between manufacturers and models within manufacturers. The primary reason for this is how the manufacturer uses the front taper, belly and rear taper to construct the line. This relationship along with several other factors determines how a given line will perform.

For example, the table below represents the difference in construction between Scientific Anglers three best selling "Mastery" floating fly lines, i.e., GPX, XPS, and XXD (Example used is a WF-6-F):

Model	Front Taper	Belly	Rear Taper
GPX	7.0'	27.0'	6'
XPS	9.3'	18.7'	8'
XXD	9.3'	31.7'	25'

As you can see, there are major differences between each of the three lines noted above. Add to this the variations in coatings (e.g., hard vs. supple, proprietary treatments, etc.) and the new "Multi-Stage" tapers used in lines such as RIO's "RIO Grand" which employs a front taper, belly, rear taper, body, and back taper, or Wulff's "Triangle Taper" which has only a front taper and a rear taper, and the game completely changes!

In simple terms, the longer the front taper, the more delicate the fly will be presented. Conversely, short front tapers will help the angler to turn over heavy or bulky flies or present a fly in windy conditions. In addition, while short bellies help load a rod faster, longer bellies allow the angler to cast further due to the ability to get more weight in the air (i.e., the first 50' of a GPX or XXD is heavier than the first 50' of an XPS).