Counter
counter for long and narrow things (e.g. guns, spades, hoes, oars, ink sticks, candles, abacuses, kitchen knives, scissors, shamisen, violins); counter for palanquins, rickshaws, and similar vehicles
私が見つけたのは1丁のハサミだけだった。I found nothing but a pair of scissors.
Also written 挺【ちょう】、梃【ちょう】