I've seen a few of these type bumpers used by rural Fire Departments of their "Brush Trucks". They provided a great platform for fighting grass and brush fires and aided in getting cargo and fire fighting equipment in the truck and out to the scene.

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There was some talk a while back on different rear bumpers available for the Forward Control Jeeps.  Craig Pensy was kind enough to send me these photos from his collection to share with everyone.  I haven't seen too many of these mounted on FC-150's, but I've seen quite a few of the FC-170 versions.  Thanks for sharing some of your literature collection with us.