Juan, these old Clark's use a "deck number" to identify the correct packing kit. If you are standing on the forks facing the machine you should see this number stampedon the outer channel about waist high. A triple mast will start with a "M" then about 4 numbers. I have done several of these through the years on the 355 trucks, a 685 is the same style, just bigger. It's pretty complicated to get out and also to disassemble.