4ecddb28c95b05f0

// import tls "github.com/refraction-networking/utls"
tcpConn, err := net.Dial("tcp", "tlsfingerprint.io:443")
if err != nil {
	fmt.Printf("net.Dial() failed: %+v\n", err)
	return
}

config := tls.Config{ServerName: "tlsfingerprint.io"}
// This fingerprint includes feature(s), not fully supported by TLS.
// uTLS client with this fingerprint will only be able to to talk to servers,
// that also do not support those features. 
tlsConn := tls.UClient(tcpConn, &tlsConfig, tls.HelloCustom)
clientHelloSpec := tls.ClientHelloSpec {
	CipherSuites: []uint16{
		tls.TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384,
		0x009f,
		tls.TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256,
		0x009e,
		0x00ff,
	},
	CompressionMethods: []byte{
		0x00, // compressionNone
		0x01
	},
	Extensions: []tls.TLSExtension{
		&tls.SupportedCurvesExtension{[]tls.CurveID{
			0x001e,
			tls.X25519,
			tls.CurveP384,
			tls.CurveP256,
			tls.CurveP521,
			0x0100,
			0x0101,
			0x000e,
			0x000d,
			0x001c,
			0x000c,
			0x000b,
			0x001b,
			0x000a,
			0x0009,
			0x0016,
			0x001a,
			0x0008,
			0x0007,
			0x0006,
			0x0015,
			0x0014,
			0x0004,
			0x0005,
			0x0013,
			0x0012,
			0x0002,
			0x0003,
			0x0001,
			0x0010,
			0x0011,
			0x000f,
		}},
		&tls.SupportedPointsExtension{SupportedPoints: []byte{
			0x00, // pointFormatUncompressed
		}},
		&tls.SignatureAlgorithmsExtension{SupportedSignatureAlgorithms: []tls.SignatureScheme{
			0x0808,
			0x0807,
			0x080b,
			0x080a,
			0x0809,
			tls.PSSWithSHA512,
			tls.PSSWithSHA384,
			tls.PSSWithSHA256,
			tls.ECDSAWithP521AndSHA512,
			tls.ECDSAWithP384AndSHA384,
			tls.ECDSAWithP256AndSHA256,
			0x0303,
			tls.PKCS1WithSHA512,
			tls.PKCS1WithSHA384,
			tls.PKCS1WithSHA256,
			0x0301,
			tls.ECDSAWithSHA1,
			0x0202,
			tls.PKCS1WithSHA1,
			0x0101,
		},},
		&tls.UtlsExtendedMasterSecretExtension{},
		&tls.SessionTicketExtension{},
		&tls.UtlsPaddingExtension{GetPaddingLen: tls.BoringPaddingStyle},
	},
}
tlsConn.ApplyPreset(&clientHelloSpec)
        
n, err = tlsConn.Write([]byte("Hello, World!"))
// or tlsConn.Handshake() for better control