|Technician: Breacher||Tier 1|
|Basic (1 pt): You fix drills and saws 25% faster. Drills and saws are also silent. Civilians and guards must see the drill or saw in order to become alerted.|
|Ace (3 pt): Gives your drills and saws a 10% chance to automatically restart after breaking.|
Getting the basic version of this skill is required to get up the Breacher skilltree. It reduces your interaction time with drills or saws required to restart them. It also renders drill completely silent. There is no way to undo this, so if you want to use loud drills to lure enemies, you need to have someone on the team without this skill.
The aced effect increases your chance to auto-restart by 10%. This can stack with a Kickstarter's Basic effect. Only one Hardware Expert upgrade can be applied at a time. This effect is applied upon placing a drill, upgrading a drill without this effect, or repairing a drill without this effect. An autorestarting drill will autorestart within 5-20 seconds of breaking down. If the drill does not become an autorestarting drill when placed or upgraded, it will never autorestart. If it does become an autorestarting drill, it will always restart. There is no middle ground. Exclusion would be if only this upgrade is applied and another player updates it with Kickstarter, making another roll. 
Non-upgraded drills, by default, have a sound radius of 25 meters. Guards or gangsters within this range will path towards the drill to investigate. If an object blocks the enemy's line of sight of the drill, this range is halved to a default distance of 12.5 meters. The basic version of this skill reduces the default sound radius to 0 meters, meaning guards and civilians must spot the drill themselves to become alerted.
It is worth noting that this skill also affects the thermal lance used in some missions.
In loud heists, the silencing effect is entirely useless, as sound radius is meaningless if the players have already been detected. On stealthy heists, this skill sees significantly more use (Firestarter Days 2 and 3, Nightclub, Big Oil, Bank Heist, Election Day, Shadow Raid, and Big Bank all benefit from this skill). However, there are some circumstances on quiet heists when loud drills are preferred over silent ones. One of the most common examples of this is the power box room on Firestarter Day 3. A loud drill can be started on this room on the roof of the bank to lure guards to a secluded area where they can be easily killed. If in doubt, it is best to consult with your team before silencing a potentially beneficial drill.
As the more practical drilling spots (security doors, safes, etc...) usually have more silent, faster and/or more efficient (but still quieter than drills nonetheless) methods of breaching like Lockpicking Expert, ECM Overdrive, or simply by means of a keycard, acquiring this skill is only recommended if one were to rely mostly on drills to open up locked doors/safes during stealth, or are trying to unlock a higher tier in the Breacher tree. However it's very useful if a titan safe must be opened silently since they can only be drilled.
- A silent drill/saw jamming still provides auditorial noise to the players, but not to NPC's. This is done due to gameplay reasons.