diff --git a/Sieve/Models/FilterTerm.cs b/Sieve/Models/FilterTerm.cs
index 826833e..b69f33f 100644
--- a/Sieve/Models/FilterTerm.cs
+++ b/Sieve/Models/FilterTerm.cs
@@ -5,6 +5,8 @@ namespace Sieve.Models
 {
     public class FilterTerm : IFilterTerm
     {
+        public FilterTerm() { }
+
         private static readonly string[] Operators = new string[] {
                     "==*",
                     "@=*",
@@ -19,23 +21,27 @@ namespace Sieve.Models
                     "_="
         };
 
-        public FilterTerm(string filter)
+        public string Filter
         {
-            var filterSplits = filter.Split(Operators, StringSplitOptions.RemoveEmptyEntries).Select(t => t.Trim()).ToArray();
-            Names = filterSplits[0].Split('|').Select(t => t.Trim()).ToArray();
-            Value = filterSplits.Length > 1 ? filterSplits[1] : null;
-            Operator = Array.Find(Operators, o => filter.Contains(o)) ?? "==";
-            OperatorParsed = GetOperatorParsed(Operator);
-            OperatorIsCaseInsensitive = Operator.Contains("*");
+            set
+            {
+                var filterSplits = value.Split(Operators, StringSplitOptions.RemoveEmptyEntries).Select(t => t.Trim()).ToArray();
+                Names = filterSplits[0].Split('|').Select(t => t.Trim()).ToArray();
+                Value = filterSplits.Length > 1 ? filterSplits[1] : null;
+                Operator = Array.Find(Operators, o => value.Contains(o)) ?? "==";
+                OperatorParsed = GetOperatorParsed(Operator);
+                OperatorIsCaseInsensitive = Operator.Contains("*");
+            }
+
         }
 
-        public string[] Names { get; }
+        public string[] Names { get; private set; }
 
-        public FilterOperator OperatorParsed { get; }
+        public FilterOperator OperatorParsed { get; private set; }
 
-        public string Value { get; }
+        public string Value { get; private set; }
 
-        public string Operator { get; }
+        public string Operator { get; private set; }
 
         private FilterOperator GetOperatorParsed(string Operator)
         {
@@ -65,6 +71,6 @@ namespace Sieve.Models
             }
         }
 
-        public bool OperatorIsCaseInsensitive { get; }
+        public bool OperatorIsCaseInsensitive { get; private set; }
     }
-}
\ No newline at end of file
+}
diff --git a/Sieve/Models/IFilterTerm.cs b/Sieve/Models/IFilterTerm.cs
index a7c2baf..a844f35 100644
--- a/Sieve/Models/IFilterTerm.cs
+++ b/Sieve/Models/IFilterTerm.cs
@@ -2,10 +2,11 @@
 {
     public interface IFilterTerm
     {
+        string Filter { set; }
         string[] Names { get; }
         string Operator { get; }
         bool OperatorIsCaseInsensitive { get; }
         FilterOperator OperatorParsed { get; }
         string Value { get; }
     }
-}
\ No newline at end of file
+}
diff --git a/Sieve/Models/ISieveModel.cs b/Sieve/Models/ISieveModel.cs
index 77e682b..f60476d 100644
--- a/Sieve/Models/ISieveModel.cs
+++ b/Sieve/Models/ISieveModel.cs
@@ -1,8 +1,14 @@
-using System.Collections.Generic;
+using System;
+using System.Collections.Generic;
 
 namespace Sieve.Models
 {
-	public interface ISieveModel<TFilterTerm, TSortTerm>
+    public interface ISieveModel : ISieveModel<IFilterTerm, ISortTerm>
+    {
+
+    }
+
+    public interface ISieveModel<TFilterTerm, TSortTerm>
         where TFilterTerm : IFilterTerm
         where TSortTerm : ISortTerm
     {
diff --git a/Sieve/Models/ISortTerm.cs b/Sieve/Models/ISortTerm.cs
index c75d30a..24f352c 100644
--- a/Sieve/Models/ISortTerm.cs
+++ b/Sieve/Models/ISortTerm.cs
@@ -2,7 +2,8 @@
 {
 	public interface ISortTerm
     {
+        string Sort { set; }
         bool Descending { get; }
         string Name { get; }
     }
-}
\ No newline at end of file
+}
diff --git a/Sieve/Models/SieveModel.cs b/Sieve/Models/SieveModel.cs
index 9483d45..1094ecc 100644
--- a/Sieve/Models/SieveModel.cs
+++ b/Sieve/Models/SieveModel.cs
@@ -1,11 +1,16 @@
-using System.Collections.Generic;
+using System;
+using System.Collections.Generic;
 using System.ComponentModel.DataAnnotations;
 using System.Runtime.Serialization;
 
 namespace Sieve.Models
 {
+    public class SieveModel : SieveModel<FilterTerm, SortTerm> { }
+
     [DataContract]
-    public class SieveModel : ISieveModel<IFilterTerm, ISortTerm>
+    public class SieveModel<TFilterTerm, TSortTerm> : ISieveModel<TFilterTerm, TSortTerm>
+        where TFilterTerm : IFilterTerm, new()
+        where TSortTerm : ISortTerm, new()
     {
         [DataMember]
         public string Filters { get; set; }
@@ -18,25 +23,33 @@ namespace Sieve.Models
 
         [DataMember, Range(1, int.MaxValue)]
         public int? PageSize { get; set; }
-
-        public List<IFilterTerm> FiltersParsed
+        
+        public List<TFilterTerm> FiltersParsed
         {
             get
             {
                 if (Filters != null)
                 {
-                    var value = new List<IFilterTerm>();
+                    var value = new List<TFilterTerm>();
                     foreach (var filter in Filters.Split(','))
                     {
                         if (filter.StartsWith("("))
                         {
                             var filterOpAndVal = filter.Substring(filter.LastIndexOf(")") + 1);
                             var subfilters = filter.Replace(filterOpAndVal, "").Replace("(", "").Replace(")", "");
-                            value.Add(new FilterTerm(subfilters + filterOpAndVal));
+                            var filterTerm = new TFilterTerm
+                            {
+                                Filter = subfilters + filterOpAndVal
+                            };
+                            value.Add(filterTerm);
                         }
                         else
                         {
-                            value.Add(new FilterTerm(filter));
+                            var filterTerm = new TFilterTerm
+                            {
+                                Filter = filter
+                            };
+                            value.Add(filterTerm);
                         }
                     }
                     return value;
@@ -48,16 +61,20 @@ namespace Sieve.Models
             }
         }
 
-        public List<ISortTerm> SortsParsed
+        public List<TSortTerm> SortsParsed
         {
             get
             {
                 if (Sorts != null)
                 {
-                    var value = new List<ISortTerm>();
+                    var value = new List<TSortTerm>();
                     foreach (var sort in Sorts.Split(','))
                     {
-                        value.Add(new SortTerm(sort));
+                        var sortTerm = new TSortTerm()
+                        {
+                            Sort = sort
+                        };
+                        value.Add(sortTerm);
                     }
                     return value;
                 }
@@ -65,6 +82,7 @@ namespace Sieve.Models
                 {
                     return null;
                 }
+
             }
         }
     }
diff --git a/Sieve/Models/SortTerm.cs b/Sieve/Models/SortTerm.cs
index 3b6b10f..4d819b6 100644
--- a/Sieve/Models/SortTerm.cs
+++ b/Sieve/Models/SortTerm.cs
@@ -2,15 +2,20 @@
 {
     public class SortTerm : ISortTerm
     {
-        private readonly string _sort;
+        public SortTerm() { }
 
-        public SortTerm(string sort)
+        private string _sort;
+        
+        public string Sort
         {
-            _sort = sort;
+            set
+            {
+                _sort = value;
+            }
         }
 
         public string Name => (_sort.StartsWith("-")) ? _sort.Substring(1) : _sort;
 
         public bool Descending => _sort.StartsWith("-");
     }
-}
\ No newline at end of file
+}
diff --git a/Sieve/Services/ISieveProcessor.cs b/Sieve/Services/ISieveProcessor.cs
index 3984cf1..6baffca 100644
--- a/Sieve/Services/ISieveProcessor.cs
+++ b/Sieve/Services/ISieveProcessor.cs
@@ -3,15 +3,22 @@ using Sieve.Models;
 
 namespace Sieve.Services
 {
-    public interface ISieveProcessor : ISieveProcessor<ISieveModel<IFilterTerm, ISortTerm>, IFilterTerm, ISortTerm>
+    public interface ISieveProcessor : ISieveProcessor<SieveModel, FilterTerm, SortTerm>
+    {
+
+    }
+
+    public interface ISieveProcessor<TFilterTerm, TSortTerm> : ISieveProcessor<SieveModel<TFilterTerm, TSortTerm>, TFilterTerm, TSortTerm>
+        where TFilterTerm : IFilterTerm, new()
+        where TSortTerm : ISortTerm, new()
     {
 
     }
 
     public interface ISieveProcessor<TSieveModel, TFilterTerm, TSortTerm>
         where TSieveModel : class, ISieveModel<TFilterTerm, TSortTerm>
-        where TFilterTerm : IFilterTerm
-        where TSortTerm : ISortTerm
+        where TFilterTerm : IFilterTerm, new()
+        where TSortTerm : ISortTerm, new()
 
     {
         IQueryable<TEntity> Apply<TEntity>(
diff --git a/Sieve/Services/SieveProcessor.cs b/Sieve/Services/SieveProcessor.cs
index 11cbcb5..4a8bcc4 100644
--- a/Sieve/Services/SieveProcessor.cs
+++ b/Sieve/Services/SieveProcessor.cs
@@ -11,7 +11,28 @@ using Sieve.Models;
 
 namespace Sieve.Services
 {
-    public class SieveProcessor : SieveProcessor<ISieveModel<IFilterTerm, ISortTerm>, IFilterTerm, ISortTerm>, ISieveProcessor
+    public class SieveProcessor : SieveProcessor<SieveModel, FilterTerm, SortTerm>, ISieveProcessor
+    {
+        public SieveProcessor(IOptions<SieveOptions> options) : base(options)
+        {
+        }
+
+        public SieveProcessor(IOptions<SieveOptions> options, ISieveCustomSortMethods customSortMethods) : base(options, customSortMethods)
+        {
+        }
+
+        public SieveProcessor(IOptions<SieveOptions> options, ISieveCustomFilterMethods customFilterMethods) : base(options, customFilterMethods)
+        {
+        }
+
+        public SieveProcessor(IOptions<SieveOptions> options, ISieveCustomSortMethods customSortMethods, ISieveCustomFilterMethods customFilterMethods) : base(options, customSortMethods, customFilterMethods)
+        {
+        }
+    }
+
+    public class SieveProcessor<TFilterTerm, TSortTerm> : SieveProcessor<SieveModel<TFilterTerm, TSortTerm>, TFilterTerm, TSortTerm>, ISieveProcessor<TFilterTerm, TSortTerm>
+        where TFilterTerm : IFilterTerm, new()
+        where TSortTerm : ISortTerm, new()
     {
         public SieveProcessor(IOptions<SieveOptions> options) : base(options)
         {
@@ -32,8 +53,8 @@ namespace Sieve.Services
 
     public class SieveProcessor<TSieveModel, TFilterTerm, TSortTerm> : ISieveProcessor<TSieveModel, TFilterTerm, TSortTerm>
         where TSieveModel : class, ISieveModel<TFilterTerm, TSortTerm>
-        where TFilterTerm : IFilterTerm
-        where TSortTerm : ISortTerm
+        where TFilterTerm : IFilterTerm, new()
+        where TSortTerm : ISortTerm, new()
     {
         private readonly IOptions<SieveOptions> _options;
         private readonly ISieveCustomSortMethods _customSortMethods;