SELECT 
  cscart_products.* 
FROM 
  cscart_products 
WHERE 
  cscart_products.product_id IN (
    10360, 10361, 10362, 10363, 10364, 10365, 
    10366, 10367, 10368, 12671, 12672, 
    15779, 12673, 12674, 12675, 12676
  )

Query time 0.00067

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "table_name": "cscart_products",
      "access_type": "range",
      "possible_keys": ["PRIMARY"],
      "key": "PRIMARY",
      "key_length": "3",
      "used_key_parts": ["product_id"],
      "rows": 16,
      "filtered": 100,
      "index_condition": "cscart_products.product_id in (10360,10361,10362,10363,10364,10365,10366,10367,10368,12671,12672,15779,12673,12674,12675,12676)"
    }
  }
}