Ring of Chameleon Power duration

How long is the bonus to Stealth granted by the Ring of Chameleon Power, supposed to last?

For reference:

Ring of Chameleon Power

Aura: faint illusion CL: 3rd
Slot: ring; Price: 12,700 gp; Weight —
Description
As a free action, the wearer of this ring can gain the ability to magically blend in with her surroundings. This provides a +10 competence bonus on her Stealth checks. As a standard action, she can also use the spell disguise self as often as she wants.
Construction
Requirements: Forge Ring, disguise self, invisibility; Cost: 6,350 gp

No duration listed should mean until you turn it off (barring anti-magic, dispel, etc).

Well, hopefully PFS judges agree.

Unlimited duration for the stealth bonus as per disguise self cast at 3rdf level for the other function, which I think is 30 mins.

Disguise Self doesn't provide a bonus to Stealth.

Also, the Disguise Self power, is explicitly at will.

Disguise Self doesn't provide a bonus to Stealth.

Also, the Disguise Self power, is explicitly at will.

That just means that the spell is invoked at will. I said absolutely nothing about Disguise Self providing a stealth bonus, that's the secondary function of the ring is to allow you to cast that spell at will, as opposed to the ring's constant primary function, said stealth bonus. Which would be cast at 3rd level, the ring's casting level. Once that's done the spell functions as it would for a 3rd level caster in all respects, including duration.

Is the Stealth bonus, functioning as a spell?

If so, then it make more sense, that it was based off Invisibility, which is 1 Min. per level.

Disguise self lasts 30 min but can be redone during that time as a standard action.

Stealth bonus lasts for 3 min but can be redone during that time as a standard action.

I don't see how the Stealth Bonus replicates a spell.

It doesn't make you invisible, and it doesn't go away if you attack.

It's not invisibility.

The Disguise Self portion is pretty cut, and dry.

No confusion about that part.

The stealth bonus part has no listed duration, or spell it revers to, thus i conclude that is is on until you turn it off. Just like other standart skill boosting items and stat boosters.

The Disguise Self at will is clear cut. CL of the Ring is 3, thus 30min duration of the spell.

Note that a +10 Competence bonus is 10,000, and a 1st level spell on command is 1,800. Add %50 for a secondary function and you get:
10,000 + 1,800 * 1.5 = 12,700. The price of the ring.

/cevah