Set of Four Brass/Bronze-Toned Commemorative Medals/Challenge Coins

This lot features four distinct commemorative medals or challenge coins, each encased individually in clear protective plastic. The coins appear to be struck from a brass or bronze-toned metal, exhibiting an antique or aged patina that highlights their raised designs. Each coin is circular, approximately 1.5 to 2 inches in diameter based on visual estimation against the background. One coin prominently features a detailed rendering of an armored vehicle, likely a military Humvee or similar tactical vehicle, framed by text that is partially legible, possibly related to military or tactical operations. Another coin depicts an airborne figure, possibly a paratrooper, suggesting a connection to military or aviation services. A third coin shows a collection of tools or equipment, possibly related to construction, engineering, or support services, with surrounding text that includes phrases like 'PRODUCTION SUPPORT SERVICE TEAM' or similar. The fourth coin showcases an intricate industrial scene, with machinery components and possibly a building facade, hinting at a theme of manufacturing or heavy industry. The relief on all coins is well-defined, indicating quality craftsmanship. There are no obvious signs of wear, scratches, or damage visible through the plastic casings, suggesting they are in very good to excellent condition. The consistent styling and material suggest they might be part of a series, perhaps distributed by a specific organization, military unit, or company. The lack of visible dates or maker's marks on the obverse makes precise dating challenging, but their style suggests a contemporary or modern production (late 20th to early 21st century).