I have quite a large collection of Japanese HID lamps which I bought from Japan. Many of them are mogul base.

I've noticed that the 200w and 250w lamps use either a bt28, ed28 or bt32 outer envelope. However, those envelopes have a neck that is longer than a standard bt28 or ed28 lamp.

I think the reason for this is they will fit better in fixtures designed for 400w bt37/ed37 lamps without adjusting the optics. Another reason could be the short neck bt28 or ed28 lamp would not fit because the neck is too short.

This seems to apply for many of their fixtures like floodlights or streetlights.

I have found documentation of fixtures listing wattages of 110-400w HID: Floodlight, Pole Light, Cobrahead

The 110w refers to an HPS or CMH lamp with a mogul base and a bt28 long neck envelope.

As far as I know, I haven't seen long neck bt28 or ed28 HID lamps used anywhere else other than Japan.