Mountain Pass Stacker Mini Mint Tender Leaf Mountain Pass Stack 5pcs The Mountain Pass Mine in California May Be the U.S. Rare Earths Game New Wooden 5 Piece Stackable Mountain Pass. An accessory to the Treetops Train Set or to be enjoyed as a tunnel toy, 5 mountain shape arches are all cut from one solid piece of rubber wood and illustrated to evoke the natural world. Age range: 3 Years And Older Product size: 8. 74 x 0. 98 x 6. 69 Weight: 0. 99 lbs