From Brotato Wiki
Item
Turret is an in-game item that can be bought from a Shop or can be found in a Crate. Most Items modify the Stats of the player, and some of them provide additional effects.
Buying the item spawns a Turret at the beginning of each wave that attacks enemies within 300 range for 10 + (80% ) damage, attacking every 0.73 seconds.
It is identical to the turret spawned by a Wrench Tier 1.
Scaling
Turrets are unaffected by Primary Stats, such as % Damage, Life Steal, Attack Speed, Crit Chance. But is affected by Engineering & Range.
Turrets are affected by Secondary Stats such as piercing and bouncing granted by the items Bandana & Ricochet. Not that turrets deal 100% even on bandana pierces, and ignores the -50% damage per pierce. Explosive Turret benefits from Explosion Damage and Size granted by Dynamite & Plastic Explosive. Turrets can inflict burning with Scared Sausage, and Snake helps Incendiary Turret inflict burn to more targets.