Extra Charge (Fallout Supplement)
From D&D Wiki
This mod extends the length of the short raygun with an extra set of capacitors and beam emitters. This gives it a +3 equipment bonus to damage rolls.
Price: 13 TU/130 Caps; Scarcity: Rare; Repair DC: 20; Time: 1 hour
Parts DC: 35; Parts Used: 10; Craft (mechanical) DC: 25; Time: 24 hours