This is a great bike but I simply don't have space for it. I believe it's a 1988 or 89 model, from the days when Mongoose was still a quality bike shop brand. I believe the Iboc Pro was 2nd from the top model, the Iboc Team.
Top tube, center to center: 21"
Seat tube, center of bottom bracket to center of top tube: 18"
I'm 5'9" and it fits me fairly well.
This example is mostly original, with Shimano Deore II components (precursor to Deore DX), 21 speed with Biopace chainrings. Double butted Tange chromoly tubing. It has plenty of little scratches but seems to have not been ridden much, so presumably these are mostly from storage and were there when I got it. A little minor surface rust in some places, but it's been stored indoors under my ownership.
I replaced the chain, grips, brake pads, cables, cable housing, and tires and repacked the bottom bracket and headset bearings. I have not repacked the wheel bearings but they feel pretty smooth. Seat seems to be original and is mediocre but functional. The stem in the photos is not original; I put it on because the bars were a bit low for me. But I have the original stem and it will be included. Pedals are Shimano and functional. Tires are not original and are some lower end OEM spec but in good shape.
Note: I am also happy to sell this as a frameset for $75, since I could use most of the parts for another project. Or if you want some partial combination of frame and parts, we can work that out, too. This is a very solid bike as is and is great for riding milder trails around town. It would also be a fine candidate for a resto-mod machine, or a commuter. I will remove the listing as soon as it's sold.