From the 20th wedding anniversary onwards, traditional gift materials are not offered every year; typically only every five years or so. The modern list differs in this respect, whereby a gift material is suggested for every year, at least up until the 30th anniversary, which possibly signifies a couples’ need to continue investing as much effort as possible into sustaining the commitment and romance in the later years of marriage.
This is a serious event in his life. He’s worked, planned, and gotten ready for this day for potential years. This calls for something for his business, something that he may one day pass down to his children when they inherit it. Custom frames for their first dollar, posh decorations for their office, or even a nice, strong bottle of top-shelf liquor with a custom label (that’s one they’ll probably bring home, but it’ll mean the world to them in their liquor cabinet).