Attention! Before buying any 5AR4, 5U4, GZ33, or GZ37, here is a hot ticket from Uncle Kevvy: Buy the Philips 5R4GYS made in Holland. Click here for info. Very rare. We got a stash of them and they are incredible. The only thing you have to do it make sure that sure you have enough height clearance... we provide you a picture illustrating the height of them so there's no surprises.
Current production made in Russia. Excellent and dependable tube. Most current products using the 5AR4 as a rectifier use this tube or the Shuguang (Chinese). The Chinese is more dependable.