Yealink SIP-T21P E2 VoIP Phone Review: Feature Rich Entry Phone Yealink are well-known for their extensive series of VoIP phones ranging from entry level gadgets to enterprise grade solutions. The Yealink T2 series include models that feature multiple telephony functions and great voice quality. The new SIP-T21P E2 VoIP phone is an entry level VoIP phone that offers functionality usually…