SELECT 
  cscart_products.*, 
  cscart_products.ebay_status, 
  cscart_products.ebay_template_id 
FROM 
  cscart_products 
WHERE 
  cscart_products.product_id IN (
    19629, 19630, 19631, 19632, 19633, 19634, 
    19635, 19636, 19637, 19638, 19639, 
    19640, 19641, 19642, 19643, 19644
  )

Query time 0.00042

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 (19629,19630,19631,19632,19633,19634,19635,19636,19637,19638,19639,19640,19641,19642,19643,19644)"
    }
  }
}