As its name suggests, the #25 handle is standard on the #25. This handle configuration is best described as a stag center piece with stacked leather on each end, and with black and metal spacers on each end of the stacked leather. The photos below are of a #25 handle—on a #25-6"—with black and sterling silver spacers (the single hilt and butt cap are fine silver on this specimen):
The #25 handle can be specified as a single chargeable option for the #12-9", #12-9" with #14 grind, and #26 (the 2011 price is $65), and can also be specified for the #27, though it's a non-chargeable option. Regardless of the model—#12-9", #12-9" with #14 grind, #25, #26, or #27—one must also specify brass or nickel silver, though this mainly applies to the single hilt and the color of the spacers. If you specify brass, the single hilt, spacers, and butt cap are brass. If you specify nickel silver, the single hilt is nickel silver, the spacers are aluminum, and the butt cap is Duralumin. If you want a nickel silver butt cap, that is an additional charge, and thus a chargeable option.
You can optionally source from Doug Cream fine silver for the single hilt and butt cap, and sterling silver for the spacers (see FAQ I-4 for details). Other than the cost of sourcing the silver, the only chargeable options are for specifying the fine silver single hilt and the fine silver butt cap (the 2011 catalog prices are $20 and $70, respectively).