The mount can handle up to 20Kg / 44 pounds of payload.
Please note that a long and heavy optical tube (E.g a 150m refractor or a 10inch Newtonian telescope) will result in greater forces on the mount’s mechanical parts and especially on the RA axis.
DEC axis can be easily balanced by sliding the telescope back and forth on the saddle plate.
A counterweight (close to 5Kg) will help the mount to better balance the load and provide better tracking. However, below 18Kg of equipment, even if the optical tube is long, the counterweights are useless.
By adding counterweights you can increase the payload of the mount up to 30 Kg (66 pounds). In this case, you will definitely need a heavy-duty tripod to avoid stability issues due to vibrations, any slight wind, etc.