The Rezkoye is a semi-concealable, lightweight survival machete capable of very quick hacks down a respectable range, allowing the user to rapidly chip away at an enemy until they die.
The near-perfect Concealment of the Rezkoye allows it to be used during stealth if the player isn't feeling too finicky about detection risk, or has other high-Concealment weapons to compensate for it.
Despite what's claimed by the description, the serrated edge of the Spetsnaz machete is not usually used as a weapon, but rather as a handsaw that wouldn't deal much damage at all were it to be used for hacking at an enemy, due to the saw teeth's shape and the blade's weight distribution.
The Rezkoye's inventory icon lacks the weight-reducing holes on the blade despite the weapon itself having them during play. The FBI Files icon also has them.
The term "rezkoye" (резкое) has a multitude of meanings, however judging by the machete's nature, it likely means "sharp" in context.