Deck A, from the Chemical Store Room, follow the first Nacelle B floor sign, go straight at the intersection and follow the corridor to a small room with a Black Egg.

Sector A Shuttle Control, opposite Shuttle Bay 2's functional shield control computer, on left windowsill.

Sector B, southernmost Escape Pod area, lying on the ground near a waste container.

Power Ops, in front of Simulation Unit 3 (not present on Hard and Impossible difficulties).

East Crew Quarters (lower level), northern room on the west wall, in a Security Crate.

Sector D, room opposite the Replicator in a Security Crate (not present on Impossible difficulty).

Cargo Bay 2B east side, 3rd level, on Constance Sanger's corpse.

Being careful though, it is possible to max out chosen weapons without putting any points into Modify skill. It's simple to waste them being careless and not having neither Maintenance nor Repair skills (nor using unbreakable weapons). There are enough French-Epstein Devices in the game to fully modify three weapons on Easy, Normal and Hard difficulties (actually, three and a half on Easy or Normal), except on Impossible difficulty where only 5 F-EDs are found. Only weapons already modified twice and melee weapons cannot be upgraded.

Each Modification to a weapon guarantees a 15% damage bonus (with the exception of first Grenade Launcher Modification that actually doubles damage of all but Disruption Grenades), along with a statistical bonus that is unique to each weapon.

The French-Epstein Device is one of the most valuable tools in the game, due to both its rarity and function. In reality, however, the weapon is modified free of charge.

F-ED uses Nanites to analyze and modify any weapon, according to its description.

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