There are graphical user interfaces and prebuilt Windows binaries available elsewhere on the Internet. NodeXL is a set of prebuilt class libraries using a custom Windows Presentation Foundation control. The robot uses a mini lidar for location and prebuilt maps of library layouts. All three were produced as kits, or for more money, prebuilt by Heathkit. The advantage of the prebuilt strategies is the ability to optimize the parameters. In South Africa a prebuilt Biogas system is manufactured and sold. It is one of the prebuilt rides in RollerCoaster Tycoon 3 and NoLimits. The midsection was prebuilt, before being floated to the shipyard.