Double Expansion Anchor – This anchor is designed for use in softer more suspect type base material where the holding values may be questionable. The double expansion anchor is designed so that the entire length of the anchor body expands and pushes against the side wall of the base material. This wide range of expansion gives the anchor a much better chance of obtaining holding values in most types of base materials.
In most situations you can use a hollow-wall anchor, which is designed to attach to the wall in the hollow spaces between the studs. Hollow-wall anchors come in a wide range of sizes and styles for use on virtually any wall, including drywall, plaster, and even hollow concrete block.
A spring line is a line run from amidships to the part of the anchor chain near the waterline, or to the pier near one or both ends of the boat or ship. Basically, if a ship is riding at a single anchor at the bow (front), the ship will swing with the wind so that she faces the wind head on.
Threaded Drywall Anchors Known by the trade names such as EZ-Ancor (not a typo!!)or Zip-It, this type of anchor is a basically a large, outside-threaded nut with a point on the end! The large threads are intended to hold strongly into drywall and will accept #6 or #8 sheet metal screws.
A toggle bolt, also known as a butterfly anchor, is a fastener for hanging things on hollow walls such as drywall. Toggle bolts have wings that open inside a hollow wall, bracing against it to hold the fastener securely. The wings are much larger than the bolt they are attached to.