Part number designation
Model Code-A (Thread size) x L(Insert length)-OD(Insert diameter) or HD(Head diameter)-S(Stud lengths)+Material+Finish
L3840-M2.5x6.0-OD4.5B
L3841-M2.5x6.0-HD6.0SS
L3842-M2.5x6.0-OD4.5-S5.0SZN
L3840 Insert,M2.5x6.0-OD4.5,Brass C3604
L3841 Insert with head,M2.5x6.0-HD6.0,Stainless steel SUS303
L3842 Insert with 5.0mm Stud,M2.5x6.0-OD4.5,Steel 1215, Zinc-nickel alloy plated