The Mark 13 bomb was nearly the same size as the Mark 6 nuclear bomb it was developed from; 61 inches in diameter and 128 inches long (150 cm by 320 cm), weighing 7,400 lb (3,300 kg).
As the Mark 13 neared production, advances in thermonuclear weapon design, particularly the Ivy Mike thermonuclear test in November 1952, made the Mark 13 obsolete.
Development continued for research purposes (the Upshot-Knothole Harry test shot came months after the first thermonuclear test in Ivy Mike), and in two variant designs, but the Mark 13 proper was never deployed.
The Mark 18 nuclear bomb also known as the Super Oralloy Bomb (or its initials SOB) utilized the 92-point Mark 13 implosion system, but a different fissile core with around 60 kilograms of highly enriched uranium (Oralloy).
This was the largest pure fission nuclear bomb ever tested, with a yield of more than 500 kilotons.