Trimble EZ Guide 250 GPS w/ AG15 Antenna Upgrade Ez guide 250 with ag15 antenna. Easy to use affordable tool for 6 - 8 inch pass to pass accuracy. 15 bright guidance LED Gives quick visual feedback to keep you on track. 4.3 inch color screen Night or day screen settings Easy data transfer of coverage maps using a USB stick. 7 guidance patterns for use with varied field shapes.