The difference is the stud pattern on the sole. FG (firm ground) uses longer studs for natural grass, AG (artificial ground) uses shorter hollow studs for 4G/3G pitches, and TF (turf) uses many small rubber studs for hard ground and indoor turf.
We stock football boots across these sole types from around $5.28 at MOQ 10. For a retailer or club the safe spread is more TF and AG pairs, because most buyers today play on artificial surfaces.
Tell us which surfaces your customers play on and we will help you pick the sole-type split for your order.