Hard Hat Suspension Head Protection Suspension Type One-Touch (4-Point) Fits Hat Size 6-1/2 to 8 For Use With Topgard(R) Compatible Hard Hat/Helmet Brand Name MSA SAFETY Compatible Hard Hat/Helmet Grainger Part Number 3RRR5 3RRR6 4LP01 4MC61 4MC63 4MC64 4MC65 4MC66 Compatible Hard Hat/Helmet Manufacturer Part Number 454712 454713 454719 454721 454722 454723 454725 454726 454728