Tests NOS National Union NU USA 6SK7GT Smooth Silver Plate Top  Get Rust Tube
- Ships in 1 business day or less.
- Calculated at Checkout
ATTENTION INTERNATIONAL BUYERS - Please Read Our Shipping Terns, Standard Shipping can take up to 3 MONTHS
Tube Type / Number: 6SK7GT
Actual Brand*: National Union NU
Printed Brand: FM Co
Quantity: 1 Piece-Single
Matching Date Codes? No
Plate Construction: Smooth Silver
Getter Construction: Top 
Country of Manufacture: USA
Visible Date Codes: SB 247 9-13 M
Lettering Condition: 75 Percent
Number of Mica Spacers: 2
Mica Spacer Shape:
Glass Coating: Clear
Engraved Base? No
Boxes (always included): All WB/Generic
Notes: Some rust on base
Tested For & Matched By: Gm (General Mutual Transconductance)
Test Results: 65
Minimum Good Value: 42
NOS Test Value: 65
Life Calculation: 100+where 65% = fail)
Tests as NOS? Yes
True NOS?* No
** Please note, many tubes will test NOS but will actually have a few hours of use on them. A truly NOS tube will have excellent getter flashing condition, no dirt/grime, usually in the original box, and no filament deposits. If a tube is listed as "tests NOS" but is listed as "not True NOS" please expect the tube to have a small amount of use *
All tubes have been tested using only the best tube testers. We have a large fleet of tube testers, and every single one of them has been calibrated within the last year by industry experts. We mainly use the Hickok TV-7D/U, but occasionally we may use a Hickok 539, 533A, or 600A.
We have a retail location located in Easthampton MA. You are more than welcome to pickup your order in person. Our typical hours are Monday - Friday 9:00 AM to 5:00 PM but we do offer extended hours so call first!
We do combine shipping. Orders placed on our website are automatically combined and calculated. Orders placed on other sites like reverb.com do not offer combined shipping. We can refund you the difference retroactively if you ask, but it's easier for everyone if you order on our website.
Typical transit times
Domestic USPS First Class Mail: 3-5 Days, includes tracking
Domestic USPS Priority Mail: 1-3 Days, includes tracking
International USPS First Class Mail: 3-6 weeks but up to 3 months! - without tracking
International USPS Priority Mail: 6-10 Days - includes tracking
INTERNATIONAL CUSTOMERS - READ
ALL international orders will be shipped by USPS First Class Mail International by default, which is the cheapest method. This shipping service is very cost-effective, but you will not be able to track your package. It usually takes 3-6 weeks for a First Class Mail International package to arrive, but can take UP TO 3 MONTHS FOR DELIVERY.
We guarantee all of our shipments, but we do ask that our customers wait 3 months before we grant a full refund due to a lost package. We have shipped thousands of items internationally using First Class Mail and while we have had plenty take months to arrive, less than 0.01% have gone missing.
DEPENDING ON YOUR COUNTRY'S POLICIES, YOU MAY BE RESPONSIBLE FOR IMPORT TAXES WHEN ORDERING OVERSEAS FROM US. WE ARE NOT RESPONSIBLE FOR ANY TAXES, DUTIES, OR CUSTOMS FEES. WE WILL NOT FALSIFY THE VALUE OF AN ITEM TO AVOID CUSTOMS TAXES. DOING SO IS ILLEGAL AND CAN RESULT IN SEIZURE OF YOUR ITEM.
Returns & Guarantees
Vintage & NOS tubes are guaranteed for 30 days from the date of purchase
New Production tubes are guaranteed for 90 days
We do not accept returns on the subjective basis of sonic qualities. If you are looking to tube roll on our dime, look elsewhere
All of our products are guaranteed unless otherwise stated. All items all guaranteed to be as described and free of any electrical or operational faults such as shorts, low test, microphonics, noise etc. Returns will be accepted for tubes that don't test as described in most cases, but we reserve the right to refuse a return if the tube was not tested properly by the customer; We also reserve the right to refuse a return if it is clear the item was used improperly. For example-a tube installed in the wrong amplifier. We will not accept returns for any cosmetic issues such as crooked bottles, dirty glass, poor boxes etc, unless item condition differs from the description nor will we accept a return for buyers remorse. If you bought the wrong item, you may return it but we will charge a 15% restocking fee.
About UsVIVA TUBES LLC142 Pleasant StSuite 402, Easthampton, MA 01027
VIVA TUBES is your source for vintage vacuum tubes. Located in the Brickyard Mill Building in Easthampton, MA, just next to the Eastworks building. With over 1,000,000 tubes and parts in our 7000 square foot warehouse, we carry everything from high-end audio tubes to HAM tubes. We also have a variety of vintage electronic parts as well as audio equipment and more! We have a vast inventory of thousands and thousands of tubes. We have a full service retail location which is the only of it's kind.
What started as a hobby several years ago to fund my (Dave Mell) obsession with tube audio, VIVA TUBES quickly grew into a full time business. Our team is still growing and we are committed to providing the best customer service and quality tubes in the business.
Shop with us and find out why the majority of our customers are repeat customers.
WE ARE ALWAYS BUYING TUBES - LARGE OR SMALL LOTS - WE CAN ACCEPT SHIPMENTS OR MAKE AN APPOINTMENT TO VIEW LOCALLY - PLEASE CONTACT
Vintage & NOS