The M-40 light repeating blaster, which had the nickname "Thunderbolt", was a type of repeating blaster manufactured by Merr-Sonn. This weapon used a bipod for stability and fired strong red energy projectiles. However, its design made it unsuitable for combat at close ranges.
Notably, Chalk favored the Thunderbolt and used it as her weapon of choice. Furthermore, the four cloaked assassins dispatched to eliminate Darth Vader on Vohai were equipped with this blaster.
A modified version of the Thunderbolt, called the Mark 7, was created in 137 ABY and became a sought-after item among pirates.