Starscream had null-rays on his arms which could be used to disable machinery or destroy objects.
Starscream's null-rays were mounted on the arms of his robot mode and wings of his vehicle mode. They functioned similarly to ranged weapons such as Megatron's fusion cannon, being able to fire energy blasts strong enough to knock Autobots as large as Bulkhead and Ultra Magnus backwards when fired at point-blank range or from a distance. Starscream could also adjust the rate and duration of each shot, firing in short bursts which peppered the environment or long streams of energy with enough blowback to shatter windows. The Starscream clones were also armed with null-rays.
Null-rays were common and Starscream's preferred weapon; they were sniper rifles fitted with zoom scopes.
After losing one of his arms in a Ground Bridge accident Starscream waited as Knock Out began suggesting upgrades to replace the missing limb; his highest recommendation for a new armament was a null ray. Starscream apparently took Knock Out's suggestion as he later used a blaster that disabled Bumblebee with one shot.