Ryobi Expand-It 18-Volt Lithium-Ion Cordless String Trimmer Power Head (Attachment Capable, Attachments, Battery and Charger NOT Included) - Walmart.com
RYOBI 40V HP Brushless Whisper Series 17 in. Cordless Battery Carbon Fiber Shaft String Trimmer (Tool-Only) RY402011BTL - The Home Depot