A wobble roller — the articulated pivoting roller used on modern trailer bunk frames to support the hull sides and bottom evenly regardless of minor variations in hull shape. The roller pivots freely in all directions, self-adjusting to the hull surface as the boat loads and unloads. Polyurethane construction is durable and gentle on fibreglass and aluminium.

Wobble rollers are used in sets along the keel and bunk rails of multi-roller trailers to cradle the hull evenly — far better for hull health than point-load bunks.