W86

The W86 was an American thermonuclear warhead with earth-penetrating characteristics (a nuclear bunker buster), intended for use on the Pershing II intermediate-range ballistic missile (IRBM).
The W86 design was canceled in September 1980 when the Pershing II missile mission shifted from destroying hardened targets to targeting soft targets at greater range. The W85 warhead, which had been developed in parallel with the W86, was used for all production Pershing II missiles.
Published design details on the W86 are vague; it has been stated that the W86 and W85 were yet more derivatives of the B61 bomb family (along with the W80, W81, and W84). All of those weapons have a maximum diameter of roughly . The later B61-11 bomb is another earth-penetrating bomb type.