How big are they?
Die-Casts come in a variety of sizes, 1:24 scale and 1:18 scale are the most common. Jada Toys, Import Racer models, mainly come in 1:24 scale and a few 1:18 scale. Dub City models come in 1:24 and 1:18 scale, usually 1:24. Hot wheels die-casts are usually 1:18 scale.
1:24 scale=approx 8"
1:18 scale=approx 10"