Control Collars

Most control collars are enchanted to affect mortals or beasts, not both. A rare few (very expensive versions) are enchanted to affect both, and these collars usually can shift in size up or down to accomodate different species.
Contrary to what some believe, Control Collars do not have mind control magic innate to them. They do reduce the willpower of those wearing the collars and magnify any control magic cast on the person or beast wearing the collar.
Depending on the strength of the collar, it either raises the difficulty of resisting magic by +1, +2, or in rare cases +3, and extends the duration of any enchantment magic against the subject wearing the collar between triple and ten times the normal spell duration.
Control Collars for mortals are primarily used by slavers but they have been used by law enforcement agents, bounty hunters, and soldiers at war.

by Me with Hero Forge

"Control Collars are the most vile magical item ever mass produced. As heinous as slavery and magical mind compulsions are in general, this magnifies the evils of both.
Prolonged use kills the soul. My great aunt was a courtesean who wore a gold Control Collar and even though she was eventually rescued, after over ten years wearing of this damned things left her listless and drained for the rest of her unnaturally short life."
Basim, Confederate Satyr And Apothecary And Reagent Dealer

"Control Collars are a crutch for mind benders to use, one best used sparingly if at all. I never use them longer than it takes to move prisoners or slaves from one holding cell to another.
Control Collars make mental compulsions easier but they do not make them guaranteed. No matter how good of a caster you are, eventually you will eventually fail a casting and with Control Collars a failure is less obvious than a casting on a traget without one. Many slaves and prisoners under a control collar have faked compliance long enough to murder their would-be domintor.
For even wealthy slave owners, these collars are too expensive to be practical to use on a regular menial laborer (unless you can catch a giant I suppose).
Some lords and ladies like to use slave collars as part of creative punishment. Many prefer their courtesians wear Control Collars. Others use them on gladiator slaves. Foolish in either case as you don't want to rely on magical control for the person who is next to you in bed and you don't want to rely on magical control for someone who is well-armed and trained in combat.
-Perxidor, dark elf enchanter

Control Collars for beasts are sometimes used by adventurers, mercenaries, performers and other non-PETA approved individuals who finds it profitable to compel animals to do their bidding.

"Given that very few theurgists outside the Testers and Stewards have the neccessary magic to control beasts, these two groups have the dragon's share of the Control Collars.
A few Testers will crow about 'a warrior should fight his own battles!' but few Testers will be opposed to slapping a control collar on any powerful predator and using them as an aid in battle. The only thing holding us back is we don't have many magical item crafters capable of making a Control Collar and most of our magic item crafters would rather make weapons and armor.
Given that mortals, even Stewards, kill and eat animals, force to them to breed on our schedule and lock them in pens, it doesn't seem like that big of a deal to slap a Control Collar on an animal.
Most Stewards talk about how it is wrong to put a Control Collar on man or beast, but the Stewards, even the Stewards of the Dominion, no especially of the Dominion, are hypocrites.
A lot of forest shrines and temples secretly have a few Control Collars buried nearby and these warriors of nature will not hesitate to slap a control collar on a giant terrifying beast if they are angry enough.
-Lysisastrata, Scourge of Penarchia

History

According to the scroll heads in Magicland, Control collars saw frequent use during the Second Age, but there is no evidence of any being used in the First Age.
But in all honesty, this seems like a thing most dragons would not have any moral compunctions about using given how they view all other mortals as lesser playthings to be used or discarded at will.
While dark elves did not invent the damn collars, they seem to have perfected the process. The dark elves have somehow managed to craft these things much cheaper than anyone else can manage. The damn dark elves export and sell Control Collars to the souless rapists and slavers throughout all of Scarterra.
I understand Uskala bought a lot and Swynfaredia and the Umeran governments bought a few. Penarchia is mostly an amoral cesspool, but most of the warlords and slavers there are too poor to afford Control Collars.
Naturally, all the nations of the Colassian Confederacy have banned Control Collars on mortals. Across the sea, to their credit, Kantoc, Apseldia, Fumaya, Meckelorn, and Stahlheim have declared the use of Control Collars on mortals as maleficium.
I'm not sure about Control Collars on beasts. I wouldn't wish one of these damn collars on mortal or beast, but I am more concerned with mortals. I guess it depends on how influential Korus is in a region. If the Stewards are strong, beastly Control Collars are probably forbidden, but if the Stewards are weak, there is no one to speak up for the beasts."
-Basim, Confederate satyr and apothecary and reagents dealer

Raw materials & Components

Typically a control collar or a variant thereof requires about 125 drams worth of durable reagents amd 125 drams of common reagents for the cheapest and simplest Controll Collars. The most powerful collars with maximum potency that works on man or beast and adjusts it's size cost about six times this in materials.
The dark elves have perfected the creation of these to the point where they only need about 80% of the magical materials.

"Ever since the War, the Confederacy has captured a lot of Control Collars. Fortunately with careful disposal over just the right temperature of forge, a skilled reagents processor can salvage about 60% of the intitial regeants and apply them them towards a less sinister magical item."
-Basim, Confederate satyr and apothecary and reagents dealer