I believe these are 18" heads IIRC... 2600VDC @ 6.5mA and all of them are single line by intention. multiline HeNes are rare, as they're usually discarded at the factory as they're considered an 'oops' in manufacturing.
Can't see the model number in the picture, but if it's the one in my sig, then it's the same one. Though mine I think is a bit more lively. There's a polarized version too though I don't think coherent ever used it. The random polarized one is rated >2mW. The linear polarized one is rated for >1mW. The coherent ones are actually made by Melles griot, just rebadged...That's why they look the same.