Bel-Art Round 0.5lb Lead Ring Flask Weight with Vikem Vinyl Coating; For 125-500ml Flasks (F18307-0005)</br></br><div style="text-align:left"><b>[Product Information]</b><br><ul><li>Vinyl-coated lead ring used to stabilize and weigh down Erlenmeyer-style flasks in water baths to reduce breakage and prevent floating and spilling</li><li>Vikem vinyl-coated non-slip surface seats securely around the neck of the flask</li><li>Cushioned surface will not scratch labware</li><li>Fits 125 to 500mL Erlenmeyer-style flasks</li><li>3.0" (76mm) outside diameter (OD)， 1.7" (43mm) inside diameter (ID)， and approximate weight of 0.5lb. (237gr)</li></ul></div></br></br></br></br></br></br></br></br></br></br></br></br></br></br></br></br></br></br></br></br><img src='http://ecx.images-amazon.com/images/I/41YCtaIoLuL.jpg' noproxy></br>