I recall buying in 1968 or 69 a "new in bag", no idea of how old the stock was, Dunlop branded rubber saddle from Klopp's Cycle in London, Ontario, Canada. It was about the same size and shape as the broken railed B17 it replaced.
Now switching to faded memory retrieval, it was reddish brown in color, had three vent holes along the top, I'm not sure if these went all the way through, silver colored rivets, Dunlop branding on the side cheeks and a riveted strip label across the back with "DUNLOP" on it. The frame was black and came with a mtaching seat post clamp. I had bag strap holes at the rear, but I cant remember if they ran through the rear of the rubber top or hung down from the cantle plate. From 30' away on a foggy day it could have been mistaken for a leather saddle.
The rubber top was firm, fairly thick and not noticeably stretchy, I remember it being thicker at the edges than the middle, I imagine it was molded or cast into the shape. I cannot remember any sign of "tire style" textile reinforcement in the rubber. It never developed any visible wear as far as I can remember other than an overall loss of shine.
I was always under the impression, maybe mistakenly, that these were made by Brooks for Dunlop, the underside looked to me to be the same as a Brooks B17, but don't think at that point in time I could tell the difference between a Brooks and an Ideal saddle unless it was labeled as such.
BTW it didn't absorb moisture and could be given a quick wipe dry and then ridden, I look back on that as it's only redeeming feature.
Marcus Coles
London, Ontario, Canada.