Our 2 - 1/2" wide sideline markers are constructed of heavy - duty 18 ounce vinyl and fasten easily to the net with Velcro® attachments. Each sideline marker has full length pocket to insert antenna. Sold in pairs only. The SSI antenna is a 72" long x 3/8" diameter solid fiberglass rod with alternating 4" bands of red and white striping on the top half. Bottom of antenna includes rounded edges to prevent snagging or tearing of sideline marker. Use separately or with sideline markers. Sold in pairs only.