A very rare original pair of Genalex KT66 tubes NOS/NIB. One tube was taken out of sealed package to be tested only ,never used. The other is still in factory sealed plastic. The unsealed tube was tested on my calibrated B&K 707 and tested 120+ where 65 is good. All tubes have the clear glass with double "0" getters and flashing at the base. These tubes should last you a few decades,They are that good. I do have a quad available if needed. Shipping included to con. US. Paypal and/or insurance is extra.