i got mine at harbor freight. by the way you'll love that spine tester, the only thing i had to tweek on mine was that the plunger on the dial indicator was too "springy" so that the weight of the arrow resting on it wasn't enough to hold it on the two supports. But it was too little to measure the force with any instrument i had. I just made two little hooks with fishing weights and coat hanger that i put on the shaft outside of the supports, this holds the arrow on the stands before you put the 2 pounds on. if your indicator doesn't have as much force as mine did, just ignore what i said.