| BALANCE SHEET COMPONENTS | 
BALANCE SHEET COMPONENTS 
  
The components of certain balance sheet amounts are as follows (in thousands): 
 |  
 | 
 | 
 | 
 | 
 | 
 | 
 | 
 | 
 
   | 
June 30, 2019  | 
   | 
December 31, 2018  | 
 
Cash, cash equivalents and restricted cash:  | 
   | 
   | 
   | 
 
Cash  | 
$  | 
21,851  | 
 
  | 
   | 
$  | 
47,323  | 
 
  | 
 
Cash equivalents  | 
86,255  | 
 
  | 
   | 
85,330  | 
 
  | 
 
   | 
108,106  | 
 
  | 
   | 
132,653  | 
 
  | 
 
Restricted cash  | 
3,000  | 
 
  | 
   | 
2,998  | 
 
  | 
 
   | 
$  | 
111,106  | 
 
  | 
   | 
$  | 
135,651  | 
 
  | 
 
Inventories:  | 
   | 
   | 
   | 
 
Finished goods  | 
$  | 
9,407  | 
 
  | 
   | 
$  | 
11,171  | 
 
  | 
 
Raw materials  | 
1,367  | 
 
  | 
   | 
1,145  | 
 
  | 
 
Reserve for obsolescence  | 
(431  | 
)  | 
   | 
(151  | 
)  | 
 
   | 
$  | 
10,343  | 
 
  | 
   | 
$  | 
12,165  | 
 
  | 
 
Other accrued expenses:  | 
   | 
   | 
   | 
 
Sales returns  | 
$  | 
387  | 
 
  | 
   | 
$  | 
801  | 
 
  | 
 
Employee-related expense  | 
2,384  | 
 
  | 
   | 
4,051  | 
 
  | 
 
Warehousing, inventory-related and other  | 
905  | 
 
  | 
   | 
1,269  | 
 
  | 
 
   | 
$  | 
3,676  | 
 
  | 
   | 
$  | 
6,121  | 
 
  | 
 
Deferred revenue:  | 
   | 
   | 
   | 
 
Unshipped product  | 
$  | 
1,215  | 
 
  | 
   | 
$  | 
4,574  | 
 
  | 
 
Auto ship advances  | 
1,983  | 
 
  | 
   | 
1,876  | 
 
  | 
 
Other  | 
192  | 
 
  | 
   | 
345  | 
 
  | 
 
   | 
$  | 
3,390  | 
 
  | 
   | 
$  | 
6,795  | 
 
  | 
 
  
 
 
 |