HSS Twist Drill Parallel Shank- dia. 4. 2mm, Type- N to IS: 5101- 1991 ( Reaffirmed 2018 ) and IS: 5099- 2003 ( Reaffirmed 2018 ), and material- XT110Mo10Co 8Cr4W2 to IS: 7291- 1981 ( Reaffirmed 2019 ). MAKEs: M/ s. INDIAN TOOL MANUFACTURERS Or M/ s. ADDISON & Co LTD/ CHENNAI Or M/ s. J. K. FILES ( INDIA ) LTD/ MUMBAI Or M/ s. MIRANDA TOOLS/ MUMBAI Other makes may also be considered based on the past performance certified by other railways, subject to conforming to the technical parameters and specifications mentioned in the description