19mm Outside diameter x 235mm long leaves a 12.5mm plug of soil
(sold individually so add 3 for a set shipping is flatrate for Express post)
Side Eject very popular Choice replacement tine for Bunnings Cyclone Lawn Aerators, your turf tines will outlast your aerator.
Cut off existing tines and Insert the 12mm mounts in the holes.
Water your lawn well and deeply for the best results.