Replaces Models: 311011 Include: 2 X 311011 Walk Behind String Mower Plastic Mow Ball Head Hex Center Dimensions: Diameter 4" & Height 3 3/4" Compatible with AFI/Fence/T4X/TR Series & GR8 224L 226L 51496 51621 TB22 TB42 TB60 XT225 PRBTB22 PRBTB25 31AH-552R729 Walk Behind String Mowers Quality materials: Made from high-quality engineering plastic nylon, it offers excellent strength and impact resistance, making it suitable for use in various harsh environments. It is resistant to aging and corrosion, ensuring smooth connection with the lawn mower and enhanced safety. Please check the dimensions and product serial number before purchase to avoid wasting your time Fits for AF100001/FT1000001/FT2001001/T4X Pilot/T4X Pulse/TR0 Pro (LMF)/TR0 Sprint (SMF)/TR1 Ser# (55MB03001-03143), (60MB06001-10198), (65MB13001-16060)/TR2 Pro / Commercial/TR2 Self Propelled/TR2 Sprint/TR3 Ser# (135969-155854) YR. (2010-2013)/TR4 YR. (Ser# 156200-Current) YR. (2013-Current)/GR8/224L/226L/51496/51621/TB22/TB42/TB60/XT225/PRBTB22/PRBTB25 31AH-552R729 Walk Behind String Mowers