557100 80” Adjustable Extension For Portable Work Stand The Fender Extender Astro Pneumatic The 557100 80” Adjustable Extension For Portable Work Stand The Fender Extender Astro Pneumatic has extension tailored for long or wide bumpers, hoods and fenders that would normally be difficult to balance on a work stand. 3 way adjustable from 77.5” to 80” in length and works on any tube design work stand. Bungee cord loop attached for tying down work piece and works best on stand height settings of 30-36” (or affixed w/ 5-6 chain lengths).