Close to Metal

Close to Metal is a companion perk in Fallout 4.

Obtaining
To gain the perk, the Sole Survivor must reach maximum affinity with Valentine after completing his personal quest.

Effects
The player character has 1 more guess to dial the password in terminals. Also, terminals have 50% less time to be reset after failed hacking.

The extra guess does not stack with the Vaultboy Science Bobblehead. Unknown whether intentional or a bug, but max number of guesses remains at 5 no matter which is gotten first.

Behind the scenes
In computing, "Close To Metal" is an idiom for the lowest level software operations of a computer. It is also the name of a beta version of a low-level programming interface developed by ATI, now the AMD Graphics Product Group.