020d21aed48e8b3a

// 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,
		tls.TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384,
		tls.DISABLED_TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384,
		tls.DISABLED_TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384,
		tls.TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA,
		tls.TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA,
		0x00a5,
		0x00a3,
		0x00a1,
		0x009f,
		0x006b,
		0x006a,
		0x0069,
		0x0068,
		0x0039,
		0x0038,
		0x0037,
		0x0036,
		0xc019,
		0xc032,
		0xc02e,
		0xc02a,
		0xc026,
		0xc00f,
		0xc005,
		tls.TLS_RSA_WITH_AES_256_GCM_SHA384,
		tls.DISABLED_TLS_RSA_WITH_AES_256_CBC_SHA256,
		tls.TLS_RSA_WITH_AES_256_CBC_SHA,
		tls.TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256,
		tls.TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256,
		tls.TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256,
		tls.TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256,
		tls.TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA,
		tls.TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA,
		0x00a4,
		0x00a2,
		0x00a0,
		0x009e,
		0x0067,
		0x0040,
		0x003f,
		0x003e,
		0x0033,
		0x0032,
		0x0031,
		0x0030,
		0xc018,
		0xc031,
		0xc02d,
		0xc029,
		0xc025,
		0xc00e,
		0xc004,
		tls.TLS_RSA_WITH_AES_128_GCM_SHA256,
		tls.TLS_RSA_WITH_AES_128_CBC_SHA256,
		tls.TLS_RSA_WITH_AES_128_CBC_SHA,
		0x0088,
		0x0087,
		0x0086,
		0x0085,
		0x0084,
		0x0045,
		0x0044,
		0x0043,
		0x0042,
		0x0041,
		0x009a,
		0x0099,
		0x0098,
		0x0097,
		0x0096,
		tls.TLS_ECDHE_RSA_WITH_RC4_128_SHA,
		tls.TLS_ECDHE_ECDSA_WITH_RC4_128_SHA,
		0xc016,
		0xc00c,
		0xc002,
		tls.TLS_RSA_WITH_RC4_128_SHA,
		0x0004,
		tls.TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA,
		0xc008,
		0x0016,
		0x0013,
		0x0010,
		0x000d,
		0xc017,
		0xc00d,
		0xc003,
		tls.TLS_RSA_WITH_3DES_EDE_CBC_SHA,
		0x00ff,
	},
	CompressionMethods: []byte{
		0x00, // compressionNone
	},
	Extensions: []tls.TLSExtension{
		&tls.SupportedPointsExtension{SupportedPoints: []byte{
			0x00, // pointFormatUncompressed
			0x01
			0x02
		}},
		&tls.SupportedCurvesExtension{[]tls.CurveID{
			tls.CurveP256,
			tls.CurveP521,
			0x001c,
			0x001b,
			tls.CurveP384,
			0x001a,
			0x0016,
			0x000e,
			0x000d,
			0x000b,
			0x000c,
			0x0009,
			0x000a,
		}},
		&tls.SessionTicketExtension{},
		&tls.SignatureAlgorithmsExtension{SupportedSignatureAlgorithms: []tls.SignatureScheme{
			tls.PKCS1WithSHA512,
			0x0602,
			tls.ECDSAWithP521AndSHA512,
			tls.PKCS1WithSHA384,
			0x0502,
			tls.ECDSAWithP384AndSHA384,
			tls.PKCS1WithSHA256,
			0x0402,
			tls.ECDSAWithP256AndSHA256,
			0x0301,
			0x0302,
			0x0303,
			tls.PKCS1WithSHA1,
			0x0202,
			tls.ECDSAWithSHA1,
		},},
		&tls.GenericExtension {Id: 0x000f}, // WARNING: UNKNOWN EXTENSION, USE AT YOUR OWN RISK
		&tls.UtlsPaddingExtension{GetPaddingLen: tls.BoringPaddingStyle},
	},
}
tlsConn.ApplyPreset(&clientHelloSpec)
        
n, err = tlsConn.Write([]byte("Hello, World!"))
// or tlsConn.Handshake() for better control