Manufacturer's Part Number: RU-4-1
Part Type: Baluns, UNUNs and Chokes
Product Line: LDG Electronics RU-4:1 200 Watt UNUNs
DXE Part Number: LDG-RU-4-1

Frequency Range: 1.8-30 MHz
Ratio: 4:1
Termination Impedance (Ohms): 200
Termination Location: Top
Termination Type: UHF female, SO-239
Enclosure Type: Standard indoor box
Enclosure Material: Plastic
Core Type: Ferrite
Power Handling (CW/SSB): 100 W/200 W
Enclosure Width: 2.500 in.
Enclosure Height: 1.250 in.
Enclosure Depth: 5.000 in.
Weight: 0.380 lbs.
Quantity: Sold individually.
Lowest Band of Operation: 1.8 MHz
Highest Band of Operation: 30 MHz

Additional Information:
Antenna Type Compatibility
Long wire with ground system
Vertical, non-resonant (43 footer)
Vertical, resonant

Mini Black Widow Up & Outter Antenna
These LDG RU-4:1 200 Watt UNUNs were designed to allow for an easy interface of 43 ft., non-resonant vertical antennas to antenna tuners via 50-ohm coaxial cable. These 200 watt peak-power UNUNs also allow for the easy matching of resonant verticals--in many cases, without the use of an antenna tuner! They may also be used with many of your antenna projects where a 4:1 match is needed.
I needed an antenna that would  quickly setup and work on multiple bands with my Elecraft KX2. I already have my Black Widow Vertical Antenna so I thought I would modify it.  My plan is to make my Mini BW Antenna in to an Up & Outter. If you would like to know more about how an Up and Outter Antenna works, click here. I'm using a pole that's only 14.5 feet high so the horizonal element will be around 38 feet or so. This most likely will give me a larger take-off angle or more close in contacts.
My Elecraft KX2 Tranceiver already has a nice antenna tuner in it so I'll use this internal tuner. This way I save lugging around a tuner!  This antenna can be used with any rig that has an internal or external antenna tuner from QRP to 100W. The entire antenna including pole and support system weighs in at only 1.3 pounds!

I just tried out the antenna today ( 9/3/2017) and the thing works fantastic!  I ran three 14-foot counterpoise wires out and one 31-foot wire out. Using my Elecraft KX2, this thing tunes great on all bands from 80m to 10m! 

I then tuned around on 40m and worked W2BPI in NY from PA 579.  I then listened on 20m and snagged UT5UJO from the Ukraine and he gave me a 579!   All this while running QRP.
First thing I did was to cut a 50-foot piece of wire for the up and out radiator wire. I copied WB3GCK's, setup at our MOC Meeting place. He later used a fifty-foot radiator wire. I already had three fourteen foot conterpoise wires. So, I made a 31-foot  wire for 80m. I then bought the below Unun from DX Engineering.
Please note *
1* The 50-foot radiator wire may be any combination up and out.  Some use a 31-foot pole     and others a shoter pole.
2* For additional information about this great antenna go to WB3GCK's Website.