HTML Meta Tag Generator

using System;
using System.Collections.Generic;
using System.Text;

namespace MetaTagGenerator
{
    class MetaTagObj
    {
        private string title;
        private string desc;
        private string keys;
        private string author;
        private string distribution;
        private string revisit;

        public string Title
        {
            get { return title; }
            set { title = value.Trim(); }
        }
        public string Desc
        {
            get { return desc; }
            set { desc = value.Trim(); }
        }
        public string Keys
        {
            get { return keys; }
            set { keys = value.Trim(); }
        }
        public string Author
        {
            get { return author; }
            set { author = value.Trim(); }
        }
        public string Distribution
        {
            get { return distribution; }
            set 
            {
                if (value.Trim() == "")
                {
                    distribution = "Global";  //default value
                    return;
                }
                distribution = value.Trim(); 
            }
        }
        public string Revisit
        {
            get { return revisit + " Days"; }
            set 
            {
                if (value.Trim() == "")
                {
                    revisit = "10";
                    return;
                }
                revisit = value.Trim();
            }
        }

        public MetaTagObj(): this("Title here", "Description Here", "", "", "", "")
        {
        }
        public MetaTagObj(string title, string desc, string keys, string author, string distribution, string revisit)
        {
            Title = title;
            Desc = desc;
            Keys = keys;
            Author = author;
            Distribution = distribution;
            Revisit = revisit;
        }
        public override string ToString()
        {
            string MetaTag = "";
            MetaTag += "<title>"+ Title + "</title>" + Environment.NewLine;
            MetaTag += "<meta name=\"description\" content=\"" + Desc + "\" />" + Environment.NewLine;
            MetaTag += "<meta name=\"keywords\" content=\"" + Keys + "\" />" + Environment.NewLine;
            MetaTag += "<meta name=\"author\" content=\"" + Author + "\" />" + Environment.NewLine;
            MetaTag += "<meta name=\"distribution\" content=\"" + Distribution + "\" />" + Environment.NewLine;
            MetaTag += "<meta name=\"revisit-after\" content=\"" + Revisit + "\" />" + Environment.NewLine;

            return MetaTag;
        }
    }
}