Long way of saying this is a Current balun that will handle very high power over 1mhz to 40mhz. It's a perfect choice to feed multiband and off center fed dipoles, Windoms and Zepps.
If currently or in the past, you have encountered SWR problems when using a 4:1 balun, you should consider the model 4115 dual core 4:1 balun. For additional information, please read this note.
Additional Photos & Models: 
Design Features:
Special mix toroid provides broadband coverage. Toroid is coated with epoxy paint for extra durablity.
The design has excellent low frequency response which makes them very efficient (98-99%). This balun performs well on 160, 80 and 40 meters where most dipoles are used but because of the short length windings, works just as well up through 10 meters. Input impedance remains essentially flat across this frequency spectrum. Competing designs can very as much as 40%, especially at lower frequencies.
2 separate bifilar windings of 14 gauge Thermaleze wire. This is NOT the enameled type (Formvar) used by my less expensive competitors. It is coated with a polyimide covering rated at a minimum of 2000v breakdown voltage. The windings are then inserted into teflon tubes which increases the total breakdown to 10,000 volts.
Typical insertion loss is < 0.2db
SO-239 connectors are silver plated with teflon insulation.
All hardware is Stainless Steel. Eyebolts and studs are 1/4"
N connector and Alternate mounting options are available in Accessories.
Because of the high efficiency, this balun will not heat up or saturate like the typical cheap current baluns using ferrite rods, beads or open air wound coax.
The balun is installed in a weatherproof 4" X 4" X 2" NEMA Box which is an ideal enclosure for those who want to mount the balun remotely.
This balun will handle continuous power of 3kw (6kw PEP) and tolerate high SWR for extended periods.
It will not heat up at rated power, using extended duty cycles or stressing load conditions.
You can see from the pictures there are three versions. One with closed eye loops to provide anchors for dipoles or with studs for use with quads and windoms. The enclosure has four legs on the back side which can be used to mount to our Balun Mounting plate for mast mounting. The balun can also be built with studs on the top or sides of the enclosure for connection to ladder line, to use with yagis or for other applications that require this connector design.
