Nape piercing
Somewhat less common are surface anchors, commonly made from surgical implant-grade titanium. A surface anchor has two parts: a base or foot which is inserted under the dermis during the piercing process and which incorporates a stem exposed to the surface, and a decorative disc or ball of jewelry which typically appears flush with the surface of the skin. Surface anchor nape piercings are most commonly found placed symmetrically on either side of the spine at the nape.
Offshore embedded anchors
Torpedo anchors feature a tubular steel pile, with or without vertical steel fins that are fitted with a conical tip and filled with scrap metal or concrete..  With heights of up to 150m, the anchor becomes completely buried within the seabed from free-fall. Full-scale field tests were performed in water depths of up to 1000m using a 762mm diameter, 12m long torpedo anchor with a dry weight of 400 kN. The torpedo anchor dropped from a height of 30m above the seabed achieved 29m in normally consolidated clay. Subsequent tests with a torpedo anchor, at 240 kN dry weight with an average tip embedment of 20m, resulted in capacities of approximately 4 times the anchor dry weight immediately following installation, which approximately doubled following 10 days of consolidation reaching an ultimate holding capacity of approximately 8 times the anchor dry weight. While the efficiencies are lower than what would be obtained with other sorts of anchor like a drag embedment anchor, this is compensated by the low cost of fabrication and ease of installation. Therefore, a series of torpedo anchors can be deployed for station-keeping of risers and other floating structures