The EFHW tuner has been retired. A few circuit boards remain and are available for $7 shipped.
How to make your Hendricks SOTA tuner work properly (PDF)
EFHW Manual (960KB PDF)
EFHW Addendum (HTML) <<must read!!
EFHW Enclosure (140KB PDF)
EFHW Board Files
These baluns are perfect for portable/field operations and weigh a little more than an ounce. Kit includes a pre-drilled plastic enclosure (3/4 x 1 1/4 x 2 1/4 inch), two gold plated binding posts, a RCA jack, two BN43-202 balun cores, and enough #24 enameled wire to wind your choice of 1:1, 4:1, or 9:1 impedance ratios. These baluns are intended for QRP use.
An RCA male to BNC female adaptor is included with each kit order/
Kits are $13 each shipped to US addresses. Two kits $24, three kits $33.
Balun Assembly (HTML)