so, a normal gum shield will obviously be to protect the teeth. and these are... these have embedded technologies, so, batteries and gyroscopes and because the teeth and the upperjaw is fixed to the skull, we can then look at how fast and how forceful the heads moving on impact. leeds beckett is leading the study, testing out several different makes to determine which they feel performs the best. we're looking at how these mouthguards perform in a laboratory, so when we hit them with a pendulum, how they perform on the field, when a player gets tackled or doesn't get tackled. so, we're looking at the force, positive force or negative, so the accuracy of them. and then it's also really important to understand the players�* fit, comfort and function, because they have to wear them. they have to embrace the new technology. this is leeds rhinos academy player mackenzie turner being tackled while wearing one of the mouthguards. and this is the data from it. on our graph here, we can see the linear acceleration, which is measured as g—force. and that corresponds