Test Sieve-300 Micron Stainless Steel Mesh with Brass Frame (Diameter 200 mm) | eBay
VWR®, Test Sieves, 300×30 mm | VWR
s-l1200.jpg
Source 300 micron stainless steel sieve with Tyler standard on m.alibaba.com
s-l1200.jpg
Amazon.com: 300 Micron Mesh Stainless Steel Dry Hopper Brewing Filter for Cornelius Kegs Corny Keg Home Brewing Father's Day Gift(2.8 x 11.8 in): Home & Kitchen
Sieve Sizes: In-Depth Guide to U.S. and Metric Sizes - Gilson Co.