There are two versions of the stone toss events, differing in allowable technique. The "BRAEMAR STONE" uses a 20-26 pound stone for men (13-18 lb for women) and does not allow any run up to the toe board or "trig" to deliver the stone. It is considered a "standing put".
In the "OPEN STONE", using a 16-22 lb stone for men (8-12 lb for women), the thrower is allowed to use any throwing style, so long as the stone is put with one hand with the stone resting cradled in the neck until released.
Most athletes use either the "glide" or "spin" techniques.