It looks like we stumped you. None of the puzzler guesses were correct, but our winner was the closest to getting it right. He guessed it was a sanitary sewer clean-out pipe, and that’s what the photo looks like, according to our source at Facilities Maintenance and Engineering. Please continue reading for the correct puzzler solution.

Your challenge is to correctly identify the item and its location from the picture below. Clue: It’s somewhere at the NCI campus at Frederick or Fort Detrick. Win a framed photograph of the Poster Puzzler and have your photo featured on the Poster website by e-mailing your guess, along with your name, e-mail address, and daytime phone number, to poster@mail.nih.gov.

The April Puzzler is a steel bar joist connecting wings 2 and 3 of Building 560, the largest laboratory building at the NCI Campus at Frederick. The bar joist supports pipes that bring carbon dioxide and nitrogen to the building, which are used for a variety of laboratory functions.

Your challenge is to correctly identify the item and its location from the picture below. Clue: It’s somewhere at the NCI campus at Frederick or Fort Detrick. Win a framed photograph of the Poster Puzzler and have your photo featured on the Poster website by e-mailing your guess, along with your name, e-mail address, and daytime phone number, to poster@mail.nih.gov. All entries must be received by Friday, June 27, 2014, and the winner will be drawn from all correct answers received by that date.

The Poster Puzzler image from the Summer 2013 edition is a frog statue, which sits under the tree between Buildings 324 and 319.