Hey guys. I'm 17 (though pretty small and child-faced for my age) and relatively physically fit for my age. I am pretty skinny though. The one thing that irks me is, while my biceps aren't a problem, if I don't flex my triceps kind of jiggle. A lot. I find this weird because I'm pretty skinny, but I guess I just need to work them out more. Any good triceps excersises you guys can recommend? I have 10 and 15 pound dumbbells as well.