Specification design pattern

Specification.cs

using System;
using System.Linq;
using System.Linq.Expressions;
using Infrastructure.Data.Extensions;

namespace Infrastructure.Data.Specification
{
	public class Specification<TEntity> : ISpecification<TEntity>
	{
		public Specification(Expression<Func<TEntity, bool>> predicate)
		{
			Predicate = predicate;
		}

		public Specification<TEntity> And(Specification<TEntity> specification)
		{
			return new Specification<TEntity>(this.Predicate.And(specification.Predicate));
		}

		public Specification<TEntity> And(Expression<Func<TEntity, bool>> predicate)
		{
			return new Specification<TEntity>(this.Predicate.And(predicate));
		}

		public Specification<TEntity> Or(Specification<TEntity> specification)
		{
			return new Specification<TEntity>(this.Predicate.Or(specification.Predicate));
		}

		public Specification<TEntity> Or(Expression<Func<TEntity, bool>> predicate)
		{
			return new Specification<TEntity>(this.Predicate.Or(predicate));
		}

		public TEntity SatisfyingEntityFrom(IQueryable<TEntity> query)
		{
			return query.Where(Predicate).SingleOrDefault();
		}

		public IQueryable<TEntity> SatisfyingEntitiesFrom(IQueryable<TEntity> query)
		{
			return query.Where(Predicate);
		}

		public Expression<Func<TEntity, bool>> Predicate
		{
			get;
			set;
		}
	}
}