24-Day Advent Calendar:Count down to Christmas with 24 individually numbered compartments! Each day, open a slot to reveal a unique metal puzzlefrom intricate Nine Linked Rings to clever Luban Locks and other mind-bending disentanglement toys. Classic Brain Teasers: Each puzzle is crafted from durable metal, built to withstand repeated solving and perfect for developing focus, fine motor skills, and cognitive flexibility in both kids and adults. Festive & Fun:Its a great way to bond over brain teasers during holiday parties, quiet evenings, or even as a classroom activity before winter break. Gift of Challenges:Searching for a unique gift? This blind box is a hit with puzzle enthusiasts, students, and anyone who loves a mental challenge. Its suitable for ages 8+ (with adult supervision for younger kids) and makes a memorable present for Christmas, birthdays, or as a thinking outside the box surprise. Quality & ReusabilityEach metal puzzle is made from sturdy, rust-resistant material, ensuring longevity. Leaper Lupin Lock Puzzle Countdown Calendar Blind Boxes in Blue