Hi,
I'm from Poland. This is my first post on the forum, but I'm not new to light sources and lighting fixtures.

 Since this is my first post, I'll start with what I think is an interesting topic.

Today I'm presenting my latest acquisition – 400W mercury vapor reflex lamps. These lamps were manufactured by Telam (a Polish company producing discharge lamps, operating under this name only until 1970) in May 1969 (as indicated by the numerical code). The lamps are coated on the inside bottom with a mirror coating and a phosphor (a rather unusual solution, especially in Poland). These lamps are extremely rare and valuable due to the limited production. From what I could find, there are no photos or videos of such a lamp online other than mine. The lamps are in very good condition and show almost no wear (one of them is practically unused, as evidenced by the arc tube). 

one of the photos for comparing the lamp size to classic 400W and 250W mercury lamps

 I hope you're interested in these lamps. If so, I invite you to join the discussion and watch the video of them being ignited on my YouTube channel.https://youtu.be/sBbMYjn2fGI?si=uyG9N2tr23YvwTC_

 Best regards from Poland🇵🇱

Welcome to Lighting-Gallery!

That lamp is definitely interesting, looks very nice, interesting shape too. Excellent Youtube channel as well, I am surprised I haven't come across it yet. You have some good stuff there.

Thanks for your interest and I'm glad you like the channel, I've been creating it for a few years now and recording some of the more interesting things in my collection and beyond .These lamps are some of the most interesting and rarest in my collection.

I have certainly known of your youtube channel after sifting through other lighting channels on youtube.