DESC: The latest telescope model from Takahashi is a truly portable design. The 90mm (3½) f/5.6 fluorite doublet apochromatic optical system is of outstanding quality, with a focal length of 504mm. The optical tube assembly is only 13.8 long, weighing 7 pounds; small enough for an airline carry-on. Not only is this instrument an excellent choice for astronomy, it can be used as a portable high-quality telescope for birding. The oversize focuser has an adapter for 2 and 1¼ diagonals, and accepts the FS series photographic adapters.