// ROH.cpp : Defines the entry point for the console application.
//


#include<iostream>
#include<vector>
#include<stdio.h>
#include<cstdio>
#include<set>
#include<stdlib.h>
#include<algorithm>
#include<queue>
#include<bitset>
#include<map>
#include<fstream>
#include<stack>
#include<utility>
#include<string>
#include<cstring>
#include<math.h>

using namespace std;

#define scan scanf
#define sscan sscanf
#define get gets
#define print printf 
#define mod 1000000007
#define ll long long
#define init int i,j,k,l,test
#define pause system("pause")
#define inf 1000000009
#define white 0
#define black 2
#define gray 1
	




char a[12][12];
int m,n;
int bs_returns_equal_or_lower(int *a,int low,int high,int s)
{
	int mid;
	int ans=-inf;
	while(low<=high)
	{
		mid=(low+high)/2;
		if(a[mid]<s)
		{
			ans=max(ans,a[mid]);
			low=mid+1;
		}
		else if(a[mid]>s)
		{
			
			high=mid-1;
		}
		else
		{
			ans=a[mid];
			break;
		}
	}
	return ans;
}
bool func(int k,int l,int i,int j,int g,int h)
{
	int b,c,d,e;
	if(k==g && l==h)
		return 1;
	
	for(b=0;b<i;b++)
	{
		for(c=0;c<j;c++)
		{
			if(a[k+b][l+c]!=a[g+b][h+c])
				break;


		}
		if(c!=j)
			break;

	}
	if(b!=i)
		return 0;
	return 1;


}

int main()
{
	init;
	scan("%d",&test);
	while(test--)
	{
		scan("%d %d",&n,&m);
		char s[100];
		get(s);
		for(i=0;i<n;i++)
		{
			get(s);
			for(j=0;j<strlen(s);j++)
				a[i][j]=s[j]-'a';
		}
		//start operation
		int ans=0;
		int temp=0;
		for(i=1;i<=n;i++)
		{
			for(j=1;j<=m;j++)
			{
				//choose of i row and j col
				//pick the one
				if(ans>=i*j)
					continue;
				for(k=0;k<=n-i;k++)
				{
					for(l=0;l<=m-j;l++)
					{
						//the start point is kxl
						temp=0;
						for(int g=0;g<=n-i;g++)
						{
							
							for(int h=0;h<=m-j;h++)
							{
								if(g<k && h<l)
									continue;
								temp+=func(k,l,i,j,g,h);
								if(temp>=2)
								{
									ans=i*j;
									break;

								}


							}
							if(ans>=i*j)
								break;

						}
						if(ans>=i*j)
							break;

					}
					if(ans>=i*j)
						break;

				}


			}

		}
		cout<<ans<<endl;
	}

	
}