The Antenna Positioners (Series 50xx) Contain The Masts And Stands, Designed To Mount The Compatible Kramay Antennas. They Are Constructed With Non-Metallic, Non-Reflective, Highest-Quality Materials That Will Not Distort Any Measurement Data. They Can Handle Varying Antenna Loads, Quick Height Adjustment And Locking Wheels To Provide Ease Of Use During Testing.