The 5 pcs set of clamps with spikes can be added to a lawn roller for aerating prior to seeding or fertilizing. It is a perfect accessory for gardeners who want to start aerating their lawn. With the spikes on the clamp, the aerator can help to reduce soil compaction and allow water, air and nutrients to get to the root system for a green and healthy lawn. Made of high quality iron, the clamps are built to last. The clamps are easy to assemble with the provided screws. Delivery includes 5 clamps. Note: Lawn roller is not included.