Compatible Model: The replacement spool line is compatible with Bosch lawn mower ART 23 SL 26 SL, the ideal replacement for models F016800569 and F016800385. 16ft/4.9m flexible spool, premium weed eater string with 1.65mm diameter easily cuts through grass and weeds. Automatic Feed Spool: The auto feed system replacement spool reduces the tediousness of manually sorting out the replacement trimmer line spool during work, it saves you time and energy. Abrasion Resistant Material: The replacement string trimmer line spool is constructed with an upgraded ABS spool and high-quality nylon thread, flexible and long service life. Efficient Cutting: The trimmer spool line compatible with Bosch lawn mower ART 23 SL 26 SL is allowing for the line to stretch and cushion on impact with hard surfaces, use centrifugal force to reduce drag, and achieve fast cutting. Package included: 4 x replacement trimmer line spool. Please wear eye protection and long pants when using this product to avoid injury. Only Suitable for tender weed grass. Tough and strong weeds please use blades to trim.