WAG Boarding Steps™ Models LM-6 and LM-6H utilize hooks to go over the gunwale. The hooks can be replaced with a crossbar for gunwales wider than 4". The crossbar is clear anodized aluminum with stainless steel attachment hardware. The bar is slotted to accept carriage bolts and knobs (by customer) to attach to the gunwale or the bar can be restrained by a boat cleat or other attachment.