NBC and TMD today (11 dec 2020) announced that they havesigned a definitive agreement for NBC to acquire TMD in a cash-and stock transaction. TMD shareholders will recive $60 per share (cash+stock) under the terms of the agreement, comprised of $33.00 per share in cash and $27.00 per share in common shares of NBC stock, base on NBC's 10 Dec 2020 closing price. The stock portion will be subject to a caller based on the Average NBC price. TMD shareholders will receive a number of shares equal to $22.32 in value if the Average NBC price is above $28.70 , TMD shareholders will save one NBC share.

specify what type of risk management device is embedded in the NBC-TMD deal.