This is a new Russell Day-Long Seat for Honda Nighthawk 750 (CB-750) 1991-2003 in vinyl, "the most durable, weather resistant and generally carefree choice" per Russell's website. The seat costs more than $700 from Russell (my loss is your gain).
I've owned several alternative seats for the Honda Nighthawk 750 (CB-750) including stock, stock with a gel insert, and several seats from Corbin. In my experience, the stock seat is comfortable for almost an hour, while the Corbin Gunfighter seat is pretty hard immediately. Inserting a layer of gel into a stock seat makes the stock seat comfortable for about an hour and a half---a better-than-nothing solution if you're on a budget. (Other options like blow-up air pads, bicycle shorts, and sheepskin or other seat pads, well they didn't work well for me).
Only the Russell Day-Long seat is comfortable for longer rides. It's also more comfortable every minute of every ride. Those wide pads around your butt are really great at taking the pressure off your sit bones. The Russell Day-Long seat is built using a stock seat pan so you know it fits your Honda Nighthawk 750 perfectly.
Some things are expensive but worth it.
Why am I selling this one? Almost as soon as I got the seat, I bought a Honda Gold Wing which, despite its weight and cost, is better for long distance riding than the Honda Nighthawk 750. Basically, this seat is unused. It needs to go to a new home where, I'm pretty sure, its new owner will learn to love it quickly.
Please note: The Russell Day-Long seat increases seat height by about 1.5" so shorter riders may not be interested, depending on your priorities. My inseam is about 30" and I was able to manage pretty well. For taller riders, the increased seat height is helpful for taking the pressure off your knees, I understand.
If interested, reply with your cell number, and I'll get back to you to host your visit at my house so you can take a look.
Also note: This item is just the seat, not the motorcycle.