[Premium Quality] Made with high quality ABS spool and durable nylon thread. Not easy to break, supports fast cutting and longer service life, can cut weeds easily and efficiently [Compatibility] compatible with Parkside: PRTA 20-Li A1-IAN 311046, PRTA 20-Li B1-IAN 330831, PRTA 20-Li B2-IAN 334231, PRTA 20-Li C3-IAN 351753, PRTA 20-Li C3-IAN 365589, PRTA 20-Li C3- IAN 385583, PRTA 20-Li C3- IAN 402319, PRT 300 A1 - IAN 360066, PRT 550 A1- IAN 311404, PRT 550 A3- IAN 330241, PRT 550 A3- IAN 351652 [High efficiency] The spool design reduces air resistance and cuts more efficiently, allowing you to 'reach hard-to-reach edges of your garden lawn. The aerodynamic shape allows the line to stretch and absorb shock on hard surfaces, providing less resistance for more efficient cuts. [Time saving] Automatic replacement of the bobbin feeding system simplifies the laborious work of manual bobbin winding. Quick and easy replacement without tools. [Package Size] You will receive 4 replacement spools that fit perfectly into the thread holes.