From the publisher's website: IMPORTANT BOOSTER NOTE: To use certain elements within this product, you must own the first "Himmelveil Sewers" release. The WorldWorksGames community asks... the WWG community receives! We’ve created an all new booster based on your requests to take your sewer diving adventures even deeper! From steampunk-like pumps to 3-D pipes and enough shacks to create an entire subterranean shanty town! Sewer to street transition walls, sewer falls, props, stairs, counters and new tiles galore! Taking advantage of our smash hit TerrainlinX build system and automated cutting support, this is a must have for any TLX collector! Just be careful where you step! Himmelveil Sewers: Booster includes all of the following: * TerrianlinX compatible design! * Includes automated cutting GSD's for Craftrobo and Silhouette SD compatible automated cutters. * "Blank" tiles including stairs down in 1", 1.5" and gridless format * Double-wide sewer tiles in 1", 1.5" and gridless format * 3 bonus tiles in 1", 1.5" and gridless format * 6 new walls in 3" and 6" lengths * Mini-walls in 1", 1.5" and 2" lengths * Free-standing and wall-mounted partitions * Wheel pump * 3D pipes * 2D counters for inset pipes, floor grates, stairs and ladders down * Balcony overflows in regular and double-wide sizes * "Sewage falls" (regular and double-wide) in two and three level heights * Wooden and cloth shanties * Crates, campfires and outflow pipes * Stairs in 1" and 1.5" widths * And as always, easy to follow instructions!