To create CONM2 elements:
On the 1D page, select the elem types panel.
or
Select Element Types from the Mesh pull-down menu.
Click mass=.
Select CONM2.
Click return.
Select the masses panel on the 1D page.
Choose create (if not already chosen).
Click on the node where CONM2 will be attached.
Fill in the mass value of CONM2 element.
Click system to assign a system to CONM2 (blank or –1 is assigned through the card editor).
Click create.
Click return.