1988 Snap-on Socket 1/4 dr. TTW12 What was it for?

[3jakes]

Got this socket on a rail with some 1/4 drive carb adjust sockets.
It's a new one to me.
Dated 1988.
It has 3 bars that would fit over a cone shape.
I see a couple on ebay for sale, but no clear idea where it would have been used.
Anybody recognize it?

 

[The Cobbler]

for tri wing tamper resistant screws

 

[Wrench97]

There were some carbs(Mopar?) that briefly used them on the mixture adjustment screws. I have that with the tune up set.

 

[3jakes]

for tri wing tamper resistant screws

That led me to these which looks about right.
Never seen these anywhere, let alone on a carb, but not a professional wrench by any means.

Tri-Groove
This unique round head with three side grooves provides high security. Tri groove screws are difficult to grab with standard pliers and require a special socket driver. When proper installation tools are used, this screw offers considerable torque with low fastener distortion and little breakage.

 

[captain14]

MOPAR also used a two wing anti-theft socket that worked on the fasteners on their AM/FM radios in the dash.

 

[Wrench97]

Yes I remember them mid 70's Cordoba/Charger radio screws.

I think there were 2 sizes TW11 & TW12 It's another one of those tools I had to buy and only use a couple times then 2 years later they change to some other obscure screw head.

The original set it had a allen socket to adjust GM points 2 slotted sockets, a GM Double D head socket the TW12 tri wing and a slotted driver. I think it changed over the years on which sockets it included here is what they sell now.

 

[Oldtuleguy]

I have one for the filler/gas cap screws on my old barracuda

 

[3jakes]

Ok, after a little more research,
The correct name for this style of security fastener is indeed Tri-Groove, T-Groove, or Tripple-groove.



Tri-Wing is actually this:

 

[genog]

I seem to remember that the ignition switch on a 92 Toyota pickup is bolted to the steering column with something like that tri-groove.
Come to think....
those bolts may not have had grooves.
Got the bolt to turn with a punch or chisel on the cone end

 

[Oldtuleguy]

Those were tamper proof bolts, the heads snap off when you tighten them.

 

[genog]

Yup