Body: Stainless steel; Window: Borosilicate. 1.5" Tri-Clamp Long Sight Glass — USA Lab. USA Lab 1.5" Tri-Clamp Sight Glass (long-body style). (1) 1.5" Tri-Clamp long sight glass assembly. Glacier Tanks 1.5" Tri-Clamp Sight Glass (inline/union type).
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