Review on 🔥 Enhanced Cooling Performance: 30 PCS Raspberry Pi 4 Heatsink Kit with Thermal Conductive Adhesive Tape, Aluminum and Copper Heat Sink for Raspberry Pi B B+ 2/3/4 by Steven Brouillard

They work as expected but I was missing 4 of the 6 copper 1mm spacers (only 2 in my pack), the rest of the parts were included. Luckily I don't really need the 1mm spacers anyway (I bought them for other finned heatsinks). However, I expect to get what was advertised. Because they're tiny, they won't do much without air movement. It's not the heatsink's fault, but if you expect significant temperature differences, you'll need something to move some air, too. The lower star rating was due to the quality control in the actual delivery of the product being sold as well as inferior adhesive. The heatsinks will stick, but don't overtighten or they may come loose.