Circular Sight Glasses by link glass

This Circular Sight Glasses is made from industry grade borosilicate glass, with a thickness of 5mm,6mm,8mm,10mm,12mm,14mm,15mm,19mm,20mm,25mm,30mm,etc. Crafted to withstand high temperatures and resist scratches, it's a durable choice for industry sight glass use, peep hole window, and more. Guaranteed quality for your professional needs.