Embodiments of a co-molded putter-type golf club head comprising a high-density chassis made of a first material and a low-density putter-type body made of a second material. The first material can be a high density metal (i.e., steel or tungsten, but not limited to). The second material can be a low density thermoplastic composite (i.e., polyphenylene sulfide (PPS), polyamide (PA), but not limited to). The chassis comprises a flow aperture, and one or more interlocking features. The putter-type body portion encases the entirety of the at least one interlocking feature. Further, the putter-type body encapsulates the chassis such that the body extends through, and completely fills the flow aperture, to interlock the body and chassis, and thus form the club head. Other embodiments may be described and claimed.