This test is used to evaluate the durability of arms due to vertical forces. The test applies to samples that have multiple seats and arms. The sample will be without inhibiting movement of the arms. If the sample has two arms, both arms will be tested. A 16 in. loading device at least the width of the arm will be attached to apply a vertical force evenly on the arm. A force of 150 lb. will be applied for 10,000 cycles on each arm. The cycle rate will be set between 10 and 30 cycles per minute.