The Pentek SH154421 is the correct replacement for the following:
The Pentek SH154421 3/4" White Filter Housing Cap is constructed from durable Polypropylene. Also known as part number SH154421, this white filter cap has a 3/4" inlet NPT/outlet connection.
Pentek Filter Housing Cap specifications:
This Pentek SH154421 Filter Housing Cap is not equipped with pressure release valve. To prevent cracking of the filter and avoid water leakage, be sure to protect your housing unit against freezing.