Here are the few GT's I currently have. There have been others over the years but I have traded away or sold some.
From Left to Right:
Bottelsen GT, 28 grams. This is the first "expensive" set of darts I ever bought and they have a lot of sentimental value even if I almost never throw them anymore. I bought them brand new in 2003 (ish), and they were already threaded for the tiny 6ba stems.
Custom (Jeff Pickup) 26 gram Copper Tungsten dart modeled on the GT. I call them my "CT's". The back end takes Bottelsen's GT screw-in stems, and the point is fixed.
Bottelsen GT, 23 grams. These darts are old enough that they do not have the threading in the stem end. I used my repointing tool to install some Voks stems that they use on their "Javalin" line of darts. They fit almost perfectly. They are just barely tight enough that I needed to use the repointer to get them in there.
Bottelsen Ringed GT, 23 grams. This is a special dart. I have only rarely seen ringed GT's. This one is old enough that there is no threading in the back end. I have thought about refitting them with Voks stems, but I do not want to take the chance that the tungsten would crack.
Bottelsen Superalloy GT, 17 gram. I love this dart. A bit on the fat side, and 2ba threaded, but I could throw it all day long. I have taken it to league nights and done well with it there too.
Voks Javalin, Steel, 17 grams. This is one of my very few non-standard material darts. It is made from steel (as opposed to tungsten or brass) and is quite light for the size.
Others that I have had in my collection include another custom fixed-point, nickel tungsten 25 gram GT, a 27 gram Bottelsen GT3, and a 24 gram GT that was both ringed and knurled! Sadly I no longer have any of those :(