Yup, I remember some NLS stuff. Many decades ago, I had an early mostly solid state model, maybe one of the first, with a state of the art digital display, using stacked planes of clear plastic with the numerals formed into them, and edge lit by bulbs such that only the selected number would show in each digit position, with a very 3-D effect, much more than with Nixies. It also had an electro-mechanical DAC, using telephone rotary stepping relays selecting precision resistors. It made a wonderful sound, clicking away as it arrived at the answer. Later, I had a couple of their 4-1/2 digit auto-ranging DMMs. They were my only and best DMMs for a long time, but eventually crapped out, and couldn't readily be fixed, since there was no info available. I think NLS is long gone, but for a while, they may have been at the forefront of the technology.
What I'm looking for now though, is something newer or current, like an OEM 5-1/2 digit DPM, if any exist, and at reasonable prices.
Ed
