SKIP
The provided content consists only of an image caption and source attribution. The article excerpt contains no substantive information about the Nylabone product review, testing methodology, findings, durability results, or any other concrete details from the actual 4-week test mentioned in the title. Without access to the full article text describing the test results, product performance, or specific observations about how the heavy chewer interacted with the toys, there is insufficient factual material to write an accurate news brief.