The key difference between interphase spacers and the AR product line is the clamp. For example, the AR Twister clamp is responsible for rotating the conductor through large angles so that galloping never gets going. The interphase spacers are designed to keep the conductors separated to avoid flashover. The net result of using the interphase spacer is that the two lines tend to gallop in synchrony.  View: Side by Side comparison AR Twister – Interphase Spacers.