Replacement pieces for the 3M Speedglas 9100 Series Welding Starter Kit include five outer protection plates two inner protection plates and an absorbent sweatband.Versatile assortment The kit includes five outside protection plates two inside protection plates and an absorbent sweatband. Protection plates replace worn and battered plates to restore the welder s quality of vision. Built to last These materials are built to help protect against the sparks and airborne debris of grinding and common welding types including stick TIG and MIG for applications such as construction metal fabrication and industrial maintenance. Cleaning and maintenance When a plate becomes pitted scratched or too dirty to clean with a soft cloth it s time to replace the plate. Outside and inside protection plates replace damaged and dirty plates and it is recommended that the outer plates be replaced at least once a week and interior plates once a month. The sweatband should be changed out once it becomes odorous or unhygienic.