Both are "FitStik" terms [edit] in the context of the website you provided [/edit].

TORSO LENGTH: Place a pencil or other short rod through the hole for the CRANK ADAPTOR. Then, with the CROSSBAR held up firmly in the crotch, adjust the FitStik to place the end of pencil in the sternal notch (the V-shaped notch between the collarbones). Read Torso Length on the SADDLE HEIGHT SCALE.

ARM LENGTH: With the arm outstretched to the side, grasp the crossbar in the hand and slide the stick so its base touches the ribs where they intersect the pectoral muscle. Read ARM LENGTH on the INSEAM SCALE.

Got it? Of course it's meaningless without a fitstik system