These are the insulators used at #1 & #2 injectors on 22RTE engines only.
They fit into the intake manifold BEFORE the injectors are installed. Yours are old and brittle and the o-ring has lived out it’s useful life. Since they are near impossible to remove without breaking them, the o-rings have probably never been replaced and could be causing a vacuum leak.
OE parts, this kit includes 2 insulators and 2 o-rings (they are only used on the #1 and #2 injectors).