From the publisher's website:
In days gone by, brave knights protected the innocent, battling the forces of evil with mighty weapons and chivalric code. Those days are gone... but there are still men and women who carry on that noble tradition. Don the tabard of the Musketeers and learn what it means to fight alongside them. The dark and the wicked shall fear your blade, for none serve justice so fiercely as the Musketeers.
--Details and rules for numerous bands of Musketeers - from the defunct Montaigne guard to the fearless Knights of Elaine - as well as their dark antitheses, the Black Tabards.
--New skills and background information, suitable for use in any campaign.
--Completely compatible with both the d20 system and 7th Sea's classic roll-and-keep rules.