Indian standard specification for black hexagon bolts, nuts, and lock nuts (diameter 6 to 39mm) and black hexagon screws (diameter range 6 to 24mm) 
Indian Standards Institution 
 - New Delhi  Indian Standards Institution  1971 
 - 11p. 
<br/><br/> IS 1363 : 1967 
<br/><br/><label>Subjects--Topical Terms: </label><br/> Bolts, Nuts and Lock Nuts Standards<br/> Standards <br/>NASA Thesaurus 
<br/><br/><label>Universal Decimal Class. No.: </label>083.7:621.882.211  / ISI