Cut to size with a hacksaw is best- they stay in the pockets better if they are the right length, and won't chafe your sail. Get the plastic caps too. If you can buy local that is sometimes best to save oversize shipping on the long ones. On some sails the batten will not go all the way to the end of the sewn pocket- there is sometimes an elastic internal end they fit into. So best to insert and measure before you cut. On my main the top two have velcro straps to hold them in, the bottom two have a sewn pocket that keeps them in.