All 6CA7/EL34/KT77 include our 6 month replacement warranty. 6ca7el34 JJ/Tesla EL34 Matched Pair Nice quality EL34 tube has slightly less bass and crisper highs than the JJ E34L. Can handle the high plate voltages found in vintage Marshalls and Good for Dyna ST70, Mk4, and Guitar amplifiers using EL34's, such as most Marshalls. JJ-EL34-MP JJ/Tesla EL34 Matched Quad Nice quality EL34 tube has slightly less bass and crisper highs than the JJ E34L. Can handle the high plate voltages found in vintage Marshalls and Good for Dyna ST70, Mk4, and Guitar amplifiers using EL34's, such as most Marshalls. JJ-EL34-MQ JJ Electronic E34L/6CA7 MATCHED PAIR JJ Electronic E34L MATCHED PAIR The E34L has a slightly higher grid voltage rating (-13.5 to-16.5 vs -10 to -13.5 volts) than the traditional EL34 vacuum tube. For the same idle plate current value, the E34L is typically biased with a more negative grid voltage than the EL34. This allows the E34L to offer more headroom (later breakup) than the traditional EL34. Blue or clear glass envelope, depending on availability. JJ Electronic E34L/6CA7 MATCHED PAIR e34lmpjj$89.95 JJ/Telsa E34L/6CA7 Matched Quad 6CA7/E34L Tesla/JJ (Slovakia) nice copy of Mullard. Good for Dyna ST70, Mk4, and English amps that use EL34. Blue or clear glass envelope, depending on availability. The JJ Electronic E34L adds more power to a standard EL34 due to its higher grid voltage rating. This increase gives the tube more headroom and a tighter response on the low end. The wide frequency response of this tube offers excellent harmonics that work in a variety of genres ranging from the cleanest cleans to rich and aggressive breakup. JJ-E34L-MQ$179.95 Triode, USA Customer Service M-F 9AM-4PM CT 1-800-774-3201 Email us Anytime: questions@triodestore.com