I have a model 316.711370 doubleline trimmer . It calls for .095 line , Ihave 300 feet of .065 line . Can I safely use this in this trimmer?

https://www.amazon.ca/s?k=LST300+spool&i=tools&ref=nb_sb_noss

https://www.blackanddecker.com/products/lawn-and-garden/lawn/string-trimmers/20v-max-lithium-12-inch-trimmeredger/lst300

https://www.toolservicenet.com/dewalt/en/Brand/c/Brand?q=:relevance:allCategories_string:Brand&sb=brand

.https://www.google.com/search?safe=off&rlz=1C1QJDB_enCA643CA644&sxsrf=ALeKk03J3juGUOXQlyTqFKF5Flou-mlVlw%3A1604860695243&ei=FzuoX9CRBe6yggeIq6T4CQ&q=B%26D+LST300%2C+type-2+replacement+spool

.

petrol -- use a 2.2 to -2.5 mm string
electric use 1.5--2.0 mm string

Cheryl, If trimmer takes .065 line any brand will work of this size. If you had to, you could also use .060".

For a lighter weight machine with the smaller 25 or 26cc engine like yours, .085" line is sufficient. .065" line is for electric trimmers and .095" line is for trimmers with the larger 30 and 32cc engines.

to many parameters and depends on what you have
the most popular is .065 .080 and .095
Look at the trimmer head to see if there are any numbers and usually some have directional arrows on the direction to wind the line

If it is like most trimmers, there is an arrow on one end or the other. The arrow shows you the direction to wind the string. There should also be a size shown. It will be in a decimal:.065, .080, .095...etc. That is the diameter of the string. Good luck...Lee

A good Rule-of-Thumb for homeowner trimmers is:

Curved shaft trimmers need to run .065-.080 diameter line while straight shaft trimmers can handle .095-.115 diameter.

Keep in mind the kind of use the machine gets and match line diameter accordingly. Larger line may fit into the spool, but the power and RPM that's available to you will suffer because of the extra weight and wind resistance.
Hope this helps!

http://www.dewaltservicenet.com/documents/English/Instruction%20Manual/244137-01,GH600.pdf

Most line trimmers will take .065 line. you can get this at lowes or home depot. Be sure to rewind it in the direction shown on the spool.

if its the newer type all you need to do is grab the black knob at the bottom of the trimmer head and pull it carefully straight towards you and it should pop off
wind line on the spool in the direction the arrow shows you there is a small hole you put the line in to start the line before you wind it it is labeled .065 or .080
wind about 10-15 feet of either .065 line or .080 line and lock the line in at the edge of the spool and thread the excess thru the hole and push spool back on and pull each line until it unhooks from where you locked it in .
this is the directions to the weedeater heads and spools mostly used on this product.

if its two lines then pull out 20 feet of new line cut it and put the two cut ends side by side and insert the cut ends into their respective holes in the spool and wind in the direction of the arrow until you wind to the loop then cut the loop lock your lines into place and thread it thru both holes keeping the lines kind of tight and push the spool onto the housing as it snaps in pull each line to unlock it from where they were held so the bump feed will work.

hope this helps you