MSA V-Gard Propionate Moulded Visor Chinguard Version Clear V-Gard Propionate Visors provide impact protection, and are good for those applications where chemical splash hazards also exist, They offer increased impact protection and superior optical quality over acetate visors, Being moulded makes them optically correct, and helps ensure they maintain good visibility and reduced eye fatigue. Their chemical and heat resistance is better as they are thicker and not as stressed as flat visors. MSA