The 36th iteration of Gun-Guides, from Gun-Guides LLC, focuses on the popular Ruger Mark IV. As with all previous guides, the Ruger Mark IV edition features a parts list, an exploded view and a set of detailed, illustrated instructions on how to takedown, clean, lubricate and reassemble the pistol. As the Mark IV is the latest in an existing line of pistols, the Ruger Mark IV Gun Guide even includes a brief history of its predecessors, including a helpful delineation of what features are new and exclusive to the model. Finally, the guide ends with a list of available accessories for the pistols, as well as handy reminders on gun safety rules and safe firearm storage. The Ruger Mark IV Gun Guide retails for $7. For more information, please visit gun-guides.com.