Indian standard dimensions for `o' rings and grooves for vacuum flanges 
Indian Standards Institution 
 - New Delhi  Indian Standards Institution  1973 
 - 7p. 
<br/><br/> IS 6838 : 1973 
<br/><br/><label>Subjects--Topical Terms: </label><br/> Standards <br/> Vacuum Flanges<br/>NASA Thesaurus 
<br/><br/><label>Universal Decimal Class. No.: </label>083.7:621.762.84  / ISI