I'm not sure if wheel weights count as an attachment or not, but here are a pair that I am just putting the finishing touches on. They started out life as the front brake rotors on the truck (98 GMC K2500) . These were destined for the scrap yard, but when I picked one up. I thought "that is one heavy brake rotor" and then the light bulb went off. I had a pair of turf tires on rims close by, so I tried them for fit and ... I don't think you could get a better fit with an improvised weight. They measure just under 12.5" in diameter and weighed 18lbs each before adding the concrete and the pipes for the mounting bolts. Finished weight is 24 lbs each, should be very close to 25 with mounting hardware. Total cost on these is under $30 Canadian for the pair, or about $1.75 US with the current value of our dollar (LOL).
wonder how lead fill would go ??