Curt 28321 Weld-On Pipe-Mount Swivel Trailer Jack 3 000 Lbs. Support Capacity por | 25 Jul 2026Curt 28321 Weld-On Pipe-Mount Swivel Trailer Jack 3 000 Lbs. Support Capacity. In our goal of being your best source for all things towing, the CURT line of trailer jacks is designed with care and manufactured with pride.