Energy Weapons - Extended Range Medium Laser
The Extended-Range Medium Laser (ER Medium Laser) focuses a powerful beam of light on targets that causes damage by melting or shattering armor off of the target.
As the name suggests, the Extended-Range variant of the Medium Laser improves the focusing system of the laser to project it to much farther ranges. The optics are less efficient, though, necessitating more input power for the same armor ablation and thus more waste heat in the weapon.
As with most Clan energy weapons, the Clans lack their own standard Medium Laser.
Description provided by Sarna.Net
In MW:PR 3051 the ER Medium Laser is the extended work horse weapon of both mechs and combat vehicles. At the expense of additional heat, the ER Medium Laser adds additional range.