How to add a tool model onto the robot model which can be generated in the moveit

Hey guys, I have downloaded the UR10 robot description(including the urdf and other components) in the ROS without a tool on the end effector. Now i have a mechanical mechanism which has been exported as a URDF in Solidworks. The problem is how can i add the mechanical mechanism as a tool on the robot end effector and open the entire model in the RVIZ? Do you have any tutorial about it?