Abh mod/Higgs Field Singularity Core
The Higgs Field Singularity Core was introduced in 0.5.3 RC5.
The Higgs Field Singularity Core increases its mass via a UI button setting. The setting takes affect when it's turned on. It automatically turns off if there's no longer a control room.
Just place it like any other part.
Cosmoteer 0.15.13 introduced new drag-speed calculations which seem to no longer recognize mass changes, hence, the mass changes no longer take effect.