The agents of SF9 are suited up for some intense drills in a new set of group teaser images for their comeback mini album, 'The Piece OF9'. 

Unlike in the 'Scene' version group teasers released yesterday, which featured a cool and collected side of SF9, the members display an air of intensity in their latest set of 'Freeze' version images. 

Meanwhile, 'The Piece OF9' will detail the journey of SF9 as they return to their base after being assigned to different missions. The group's 12th mini album will be out on January 9 at 6 PM KST.