The mfj-868b is, World's largest SWR / wattmeter. World's largest hf SWR/wattmeter measures a giant 6.World`s largest hf+6m SWR/wattmeter measures a giant 6½ inches diagonally across the meter scale! It Covers 1.8-54 MHz. This one you can see! Its huge scale gives you ultra-fine resolution and its big, high-contrast numbers make reading a breeze -- even across your shack. The meter needle position and motion give you an accurate indication of what's going on quickly without actually reading the scale -- like your analog watch. True peak reading circuit mfj`s exclusive true active peak reading circuit captures true peak or average forward and reflected power readings. Has 20/200/ 2000 watt ranges make it valuable for QRP qro operation. Full SWR scale, the full SWR scale makes reading SWR much more accurate and easier to read. Power saver circuit exclusive mfj wattmeter power saver circuit turns on meter only when rf power is being measured. It Covers 1.8-54 MHz. Use a 9-volt battery or 12 VDC or 110 vac with optional mfj-1312d. Cabinet measures 7w x 5 1/2h x 5d inches.