| Summary of temporary differences | 
At November 30, 2018 and November 30, 2017, respectively, the Company had temporary differences arising from the following:
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   | 
   | 
November 30, 2018  | 
   | 
November 30, 2017  | 
 
Type  | 
   | 
Amount  | 
   | 
Deferred Tax  | 
   | 
Amount  | 
   | 
Deferred Tax  | 
 
Depreciation  | 
   | 
$  | 
(379,909  | 
)  | 
   | 
$  | 
(90,802  | 
)  | 
   | 
$  | 
(378,580  | 
)  | 
   | 
$  | 
(137,992  | 
)  | 
 
Reserve for bad debts  | 
   | 
10,489  | 
 
  | 
   | 
2,507  | 
 
  | 
   | 
6,629  | 
 
  | 
   | 
2,416  | 
 
  | 
 
Reserve for returns  | 
   | 
182,692  | 
 
  | 
   | 
43,665  | 
 
  | 
   | 
246,513  | 
 
  | 
   | 
89,854  | 
 
  | 
 
Accrued returns  | 
   | 
96,592  | 
 
  | 
   | 
23,086  | 
 
  | 
   | 
109,646  | 
 
  | 
   | 
39,966  | 
 
  | 
 
Reserve for obsolete inventory  | 
   | 
25,483  | 
 
  | 
   | 
6,091  | 
 
  | 
   | 
158,269  | 
 
  | 
   | 
57,689  | 
 
  | 
 
Vacation accrual  | 
   | 
81,005  | 
 
  | 
   | 
19,361  | 
 
  | 
   | 
70,856  | 
 
  | 
   | 
25,827  | 
 
  | 
 
Alternative minimum tax carry forward  | 
   | 
—  | 
 
  | 
   | 
103,040  | 
 
  | 
   | 
—  | 
 
  | 
   | 
122,360  | 
 
  | 
 
Research and development credit carry forward  | 
   | 
—  | 
 
  | 
   | 
65,175  | 
 
  | 
   | 
—  | 
 
  | 
   | 
—  | 
 
  | 
 
Deferred compensation  | 
   | 
351,764  | 
 
  | 
   | 
84,075  | 
 
  | 
   | 
487,061  | 
 
  | 
   | 
177,534  | 
 
  | 
 
Bonus obligations unpaid   | 
   | 
70,686  | 
 
  | 
   | 
16,895  | 
 
  | 
   | 
400,166  | 
 
  | 
   | 
145,861  | 
 
  | 
 
Charitable contributions  | 
   | 
245,650  | 
 
  | 
   | 
58,713  | 
 
  | 
   | 
305,633  | 
 
  | 
   | 
111,403  | 
 
  | 
 
Section 263A costs  | 
   | 
206,283  | 
 
  | 
   | 
49,304  | 
 
  | 
   | 
48,317  | 
 
  | 
   | 
17,612  | 
 
  | 
 
Loss carry forward  | 
   | 
24,277,762  | 
 
  | 
   | 
5,768,532  | 
 
  | 
   | 
24,279,259  | 
 
  | 
   | 
8,849,789  | 
 
  | 
 
Net deferred tax asset   | 
   | 
$  | 
25,168,497  | 
 
  | 
   | 
$  | 
6,149,642  | 
 
  | 
   | 
$  | 
25,733,769  | 
 
  | 
   | 
$  | 
9,502,319  | 
 
  | 
 
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   | 
   | 
 
  
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| Schedule of income tax expense | 
Income tax expense (benefit) is made up of the following components:
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   | 
   | 
November 30,  | 
 
 
  | 
   | 
2018  | 
   | 
2017  | 
   | 
 
Current tax - Federal  | 
   | 
$  | 
17,382  | 
 
  | 
   | 
$  | 
105,770  | 
 
  | 
   | 
 
Current tax - State and Local  | 
   | 
10,210  | 
 
  | 
   | 
5,640  | 
 
  | 
   | 
 
Deferred tax expense   | 
   | 
3,352,676  | 
 
  | 
   | 
1,062,144  | 
 
  | 
   | 
 
   | 
   | 
$  | 
3,380,268  | 
 
  | 
   | 
$  | 
1,173,554  | 
 
  | 
   | 
 
  
  
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| Provision for income taxes computed at the statutory rate | 
A reconciliation of the (benefit from) provision for income taxes computed at the statutory rate to the effective rate for the years ended November 30, 2018 and 2017 is as follows:   
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   | 
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   | 
   | 
2018  | 
   | 
2017  | 
   | 
 
   | 
   | 
Amount  | 
   | 
Percent of Pretax Income  | 
   | 
Amount  | 
   | 
Percent of Pretax Income  | 
   | 
 
   | 
   | 
   | 
   | 
   | 
   | 
   | 
   | 
   | 
   | 
 
Provision for (benefit from) income taxes at federal statutory rate  | 
   | 
$  | 
12,285  | 
 
  | 
   | 
21.00  | 
%  | 
   | 
$  | 
1,021,610  | 
 
  | 
   | 
34.00  | 
%  | 
   | 
 
Changes in provision for (benefit from) income taxes resulting from:  | 
   | 
   | 
   | 
   | 
   | 
   | 
   | 
   | 
   | 
 
State income taxes, net of federal income tax benefit  | 
   | 
1,697  | 
 
  | 
   | 
2.90  | 
%  | 
   | 
73,616  | 
 
  | 
   | 
2.45  | 
%  | 
   | 
 
Change in tax rate related to future deferred tax benefits  | 
   | 
3,146,636  | 
 
  | 
   | 
5,378.68  | 
%  | 
   | 
—  | 
 
  | 
   | 
—  | 
%  | 
   | 
 
Non-deductible expenses and other adjustments  | 
   | 
219,650  | 
 
  | 
   | 
375.46  | 
%  | 
   | 
78,328  | 
 
  | 
   | 
2.61  | 
%  | 
   | 
 
Provision for (benefit from) income taxes at effective rate  | 
   | 
$  | 
3,380,268  | 
 
  | 
   | 
5,778.04  | 
%  | 
   | 
$  | 
1,173,554  | 
 
  | 
   | 
39.06  | 
%  | 
   | 
 
  
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