diff --git a/tpm.go b/tpm.go
index ca31a8f..87418c1 100644
--- a/tpm.go
+++ b/tpm.go
@@ -260,7 +260,8 @@ func (t *TPM) createLocked(opts ...KeyOption) ([]byte, error) {
 		}
 
 	case TypeECC:
-		unique := make([]byte, 64)
+		uniqueSize := opt.curve.Params().BitSize / 8
+		unique := make([]byte, 2*uniqueSize)
 		if _, err := io.ReadFull(rand.Reader, unique); err != nil {
 			return nil, fmt.Errorf("rand: %w", err)
 		}
@@ -307,8 +308,8 @@ func (t *TPM) createLocked(opts ...KeyOption) ([]byte, error) {
 			Unique: tpm2.NewTPMUPublicID(
 				tpm2.TPMAlgECC,
 				&tpm2.TPMSECCPoint{
-					X: tpm2.TPM2BECCParameter{Buffer: unique[:32]},
-					Y: tpm2.TPM2BECCParameter{Buffer: unique[32:]},
+					X: tpm2.TPM2BECCParameter{Buffer: unique[:uniqueSize]},
+					Y: tpm2.TPM2BECCParameter{Buffer: unique[uniqueSize:]},
 				},
 			),
 		}
@@ -433,9 +434,6 @@ func (t *TPM) unmarshalLocked(in []byte) (*Key, error) {
 		pub:  *pub,
 		keyb: in,
 	}
-	if t.loadedKey == out.id {
-		t.flushLocked()
-	}
 	if err := out.loadLocked(); err != nil {
 		return nil, err
 	}
diff --git a/tpm_test.go b/tpm_test.go
index 59836ab..db9b1e5 100644
--- a/tpm_test.go
+++ b/tpm_test.go
@@ -139,6 +139,9 @@ func TestECC(t *testing.T) {
 		}
 
 		pub := key.Public()
+		if got, want := pub.(*ecdsa.PublicKey).Curve.Params().BitSize, curve.Params().BitSize; got != want {
+			t.Fatalf("pub.Curve.Params().BitSize = %d, want %d", got, want)
+		}
 		hashed := sha256.Sum256([]byte(payload))
 		sig, err := key.Sign(nil, hashed[:], crypto.SHA256)
 		if err != nil {