A lead frame assembly is disclosed in which holes may be formed in contacts of the assembly and a dielectric material extends along a length of the contact. The dielectric material may be further secured to the contact by filling the hole. The dielectric material may span across two or more contacts of the lead frame assembly and also across gaps formed between the contacts, or may span across an entire side of a lead frame assembly. The dielectric material may add mechanical strength and robustness to the lead frame assembly while helping to reduce dust accumulation on electrical contacts of the assembly. The dielectric material may abut only one side of one or more contacts in the lead frame assembly and thus may not affect edge-coupling effect of contacts that form differential signal pairs.