These are a unique, featured product to this new and improved clothesline system. You never have to find extra space for them or rummage through your clothespin basket again. When you purchase a clothesline pulley system of Skyline Enterprises, 1 line spacer is included. Others are available for purchase depending on your needs. But, unlike other systems, these line spacers remain on your line once installed and provide support at all times. We recommend 1 spacer every 20′-30′.