diff --git a/src/protocol/Packet.h b/src/protocol/Packet.h
index dce57ff..9a796d9 100644
--- a/src/protocol/Packet.h
+++ b/src/protocol/Packet.h
@@ -449,12 +449,12 @@ namespace ts {
                     this->packet_id_bytes[1] = id & 0xFFU;
                 }
 
-                [[nodiscard]] inline auto packet_id() const {
+                [[nodiscard]] inline uint16_t packet_id() const {
                     return (uint16_t) (this->packet_id_bytes[0] << 8U) | this->packet_id_bytes[1];
                 }
 
                 [[nodiscard]] inline auto packet_type() const {
-                    return (PacketType) (this->type_and_flags & 0xF);
+                    return (PacketType) (this->type_and_flags & 0xFU);
                 }
             private:
                 void object_freed();