Video instructions below. This is a new high quality plug to replace the old rubber plug on your 16"-18" vintage Lava "The Wave" Machine (rectangular vessels only). This plug is necessary if you are removing the original plug on one of these vessels to replace the fluids with one of the Hughes Wave Fluid Refill Kits or for general leak repair. Most of the old plugs have hardened over the years and immediately lose their sealing ability when removed. Requires a thin flathead screwdriver to install. You can watch the video instructions above. Ships via regular US Mail in a stamped envelope without tracking. Shipping time is 2-3 business days. How to Install a Replacement Plug Lava Wave Machine Lava Wave Machine www.WaveMotionMachines.com Video will open in a new window Using the App? Paste link into a browser window: [isdntekvideo]