Winia Enterprises is a multi-divisional firm that makes and sells personal protective equipment to health-care providers and other businesses.

Division A manufactures large, state-of-the-art HEPA (high-efficiency particulate air) filters that trap harmful particles. Division A sells HEPA filters to external buyers at the price of $73 per unit. Division A also provides these HEPA filters to Division B; Division B installs these filters in medical-grade Air Purifier Units and sells these Air Purifier Units to external buyers at the price of $746 per unit.

Divisions A and B use normal absorption costing, with overhead (all fixed) allocated to units using a sophisticated activity-based costing system. Inventoriable unit costs for the two divisions are:

Division A's HEPA Filters: absorption cost per unit for external sales of $48 (includes $7 fixed overhead allocation); absorption cost per unit for internal transfers of $34 (includes $6 fixed overhead allocation).

Division B's Air Purifier Units: absorption cost per unit of $358 (includes $103 fixed overhead allocation).

Selling costs for the two divisions are:

Division A's HEPA Filters: variable selling cost for external sales of $13 per unit; no variable selling cost for internal transfers; fixed selling expenses of$347,000 per year;

Division B's Air Purifier Units: variable selling cost for external sales of $73 per unit; fixed selling expenses of $891,000 per year.

Division A has significant idle capacity, sufficient to meet all of Division B's demand for internally transferred HEPA filters. There are many other suppliers of HEPA filters suitable for Division B; Division B's top management is free to choose between internally sourced and externally purchased filters.

If two divisions use negotiated transfer pricing, what is the minimum transfer price per unit acceptable to division A?