“Tetrix” is the original robotics kit for FTC. Manufactured by Pitsco Inc. ranging from $100-$600+. Here is the FTC Competition Kit, and its complete parts list. The kit consists of high-grade aluminium C-Channels, brackets, connectors, motors, wheels, sprockets, gears, nuts, and bolts etc. A list of extra parts to be bought separately can be found here. The Tetrix motors are very compatible with LEGO Mindstorm NXTs, but as of 2015-2016, a new android based platform is being used to control the robots.
Assembly of tetrix parts is very easy. The familiar patterns on each C-Channel has screw holes at every 15 degree angle, allowing some flexibility when building yet retaining structural strength. Bolts of various lengths are screwed in using different sized Allen keys. A good practice to identify these keys is to color code them with whichever paint or electrical tape your team has lying around. The 4 most common sizes for Allen keys in Tetrix are 7/64″, 3/32″, 5/64, and 1/16″. To get hard to reach bolts, a set of T-Handles or Ball-Ended drivers is very useful to own. For quick assembly/dissasembly, it is also possible to cut the ‘L’ of a set of keys, and insert it into a drill chuck at a low clutch. This is not recommended, as it could be very dangerous to you and your robot.