I hate to disagree with Davec2 and mr. no gold but Pecards is to be avoided on antique and collector leather goods - it contains petroleum (read the label, its on there) and will eventually damage the leather. It does have it's supporters but I know of no museums that have trained conservators on staff that will use it. I recently saw in the catalog of a well known and respected militaria dealer this description of a WW1 British leather battle jerkin, "This item, sadly, has been Pecarded to death".
I myself use
pure neatsfoot oil, not neatsfoot oil compound, as Micah says, there are things in there that we don't want. I know that many seem to have a problem with neatsfoot oil but it is what I was taught to use by the harness maker who I learned from and, used properly, it does an excellent job. Yes, it darkens leather but a little goes a long way so don't overdo it. For an item that sees constant heavy use it should be applied twice a year
after cleaning. For an item that sees occasional use, it can be applied once every two years. Again, apply lightly, don't drown the item. Lexol is good, it is water based and seems to do less harm than many of the so-called "mink oil" or snow seal preparations. Always check the label to see what the preparation contains - if it has petroleum products or byproducts, find something else. Another good item is Ko-Cho-Line Leather Dressing out of England and it seems to do a good job, if I remember correctly it contains lanolin.
I do have to say that Pecards and mink oil and others do a fine job when used on everyday use boots and shoes as well as items that do not fall under the collector heading. These items can be used until worn out and then thrown away, no harm done.
For items that fall under the heading of antique or collector's goods, doing nothing is best. Keep the piece out of direct sunlight in a comfortable 60% humidity and a comfortable temperature and handle it carefully and you will notice a halt in deterioration.
Hopefully Chuck will chime in with his advice, he is the most knowledgeable member here when it comes to leather and his opinion is gold, follow him and you can't go wrong. (Even if he disagrees with me.
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