Putting weight accessories at the focus of a telescope can cause the optical tube to be unbalanced backwards and avoid balancing the mount correctly. So, Takahashi proposes specific counterweights for the optical tubes of these Mewlon telescopes, in particular the Mewlon-300CRS whose centre of gravity is, due to the size and weight of the primary mirror cell, naturally offset towards the rear.
Takahashi counterweights are made of cast aluminium. The finishing of each counterweight is done manually. These counterweights are inserted in a rail fixed under the Mewlon optical tube. They are tightened by means of a metal screw pressing on the rail. A removable central screw serves as a fall protection in case the counterweight slips on the rail.