It really depends on their design Rick. Not to sound like a TV commercial, but Fortress anchors are manufactured here in the USA using precision-machining. This simply means that they are very sharp and better able to dig faster and deeper into most bottoms.There is a setting technique that should be used with all anchors:1. Your boat should be stopped or drifting back super slow (like 1/2 mile per hour) while you deploy the anchor and let out the line that will give you a scope of 5:1. 2. Once the line is out and safely secured, continue to allow the boat to fall back (again, super slow). At some point the boat will stop falling back because the anchor will have started to dig in to the point that it is providing enough holding power to hold the boat. 3. Let things stay that way for several seconds. The boat must not be moving back, it is just staying in one place. 4. Now you can start to very gently increase the load by momentarily putting the engine in reverse, and then back to neutral. Again, the anchor should be holding the boat from falling back. 5. Once this is the case, then put additional load on the anchor by leaving the engine in reverse a little longer. 6. Next you should be able to put the engine in reverse at idle, and leave it in reverse, the boat should not be moving back because the anchor is dug in and providing holding power in excess of the pull from the engine. 7. You should then very slowly start to increase the engine rpm while in reverse. This slow, steady pull on the anchor will cause it to dig deeper and deeper, and as this happens the holding power is going up and up. You should now be able to sit there with the engine in reverse with a fair amount of power and the boat is not moving back. This is because the anchor is holding more than the pull from the engine.This technique is called "power setting" the anchor.This is standard procedure for the US Navy. It applies equally to all anchor types, and there are no exceptions.There are two issues here: 1. By applying a very gradual pull on the anchor, you are giving it a chance to start to dig in. By slowly increasing the pull you are allowing the anchor to continue to dig deeper and deeper, which in turn is giving you more and more holding power.2. The anchor must be set and the only way to know if it is set is by carefully observing that the boat is not continuing to fall back, even when you increase the pull through the use of your engine.Now in the case of many sailboats that do not have such large engines, the scenario is this: After carefully and slowly increasing the load with the engine in reverse you should reach the point when the engine is at full power, and the water is boiling out from both sides.The boat is vibrating and making considerable noise, and all the while the boat is standing still and not falling back because the anchor is holding more than the engine can pull.There is a real bonus that results from all of this and it is this:Once an anchor (any anchor) has been power set to a certain load and then the load is relaxed, the bottom will heal itself around the anchor and the holding power an hour later will be close to twice what it was!Other tips: Always use a minimum scope of 5:1. It is true that you can go up to 10:1 and get more holding power, but 5:1 will generally serve you very well. If you are in close quarters, use 5:1 and power set the anchor, then shorten the scope to no less than 3:1.