i had this trailer built 4 years ago by us steel products in portland. the inside box dimensions are 12'l x 6'9"w x 2'6"d. the box capacity (by volume) is 7.5 cubic yards. 235/80r16 tires with 8 lug rims. electric tongue jack (lighted). battery and hydraulic tank are located underneath the dump box leaving the tongue mounted tool box open for actual tool storage. trailer has an exterior remote battery post.if the trailer battery goes dead, attach jumper cables to remote post allowing the dump box to be raised for dead battery access. trailer brakes and "break away" emergency brakes. "barn door" style rear gates. dual hydraulic "rams" for superior lift capacity. integral tarp system for covering loads. spare tire. twin ramps (stored over each fender) for loading and unloading equipment. replaceable 2"x4" (wood) front rail cap for equipment bucket rest. adjustable "bull dog" style hitch (hitch has 3 different elevation settings). 8000 lb axles. recommended gross trailer weight is 12,500 lbs. recommended vertical tongue load @ ball is 1,875 lbs. asking $5700 obo. if interested contact me @ 503 849 5585