the trail gear ones can be either weld on or bolt on, if you chose to bolt them on you will have to drill through the frame and buy your own bolts, but their mounting plates are already drilled for the bolt on app. bolt on will work just fine, 6-8 grade 8 bolts could easily hold the entire weight of your vehicle. but welding them on would be easier and faster and just as good, or better... id really look at trail gear, i had a local company make mine for me, i am their test mule other wise id of gone with trail gear.