Xiao Ming has a piece of cardboard with a length of 28 cm and a width of 20 cm in his hand. After cutting off a small square with a side length of 4 cm from the four corners, fold it into a small rectangular box without a cover. How many items can this box hold?
小明手中有一张长28厘米，宽20厘米的卡纸，从四个角都剪掉边长为4厘米的小正方形后，折成一个长方体无盖的小盒子，这个盒子能容纳多少物品？
<gadget id="calculator">4 * 2</gadget>
<output>8</output>

<gadget id="calculator">28 - 8</gadget>
<output>20</output>

<gadget id="calculator">20 - 8</gadget>
<output>12</output>

<gadget id="calculator">20 * 12 * 4</gadget>
<output>960</output>

<result>960</result>