A trading strategy involving the purchase of four European call options in equal quantities. The strategy is designed to be in-the-money at maturity if the spot price is within a narrow range, with no downside loss (other than premium) if the spot price at maturity falls outside of this range on either side. To construct the strategy, a call option is purchased (long) with strike (X - n), another call option is purchased (long) with strike (X + n), and two call options are sold (short) with strike X, where X is the current spot price. The trade is directionneutral, and the maximum profit is realised when the price of the underlying is X at maturity.