Leonin Bola is a common Artifact — Equipment card from Darksteel (DST), collector number 127. Current market price: $0.10 (foil $0.48), TCGplayer market prices via Scryfall.
Equipped creature has "{T}, Unattach Leonin Bola: Tap target creature." Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)