SELECT 
  cscart_products.* 
FROM 
  cscart_products 
WHERE 
  cscart_products.product_id IN (
    12629, 10095, 10195, 10194, 10193, 10190, 
    10496, 10198, 10202, 10201, 10200, 
    10227, 10226, 10651, 9945, 10642, 10601, 
    9727, 9728, 9729
  )

Query time 0.00040

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": 20,
      "filtered": 100,
      "index_condition": "cscart_products.product_id in (12629,10095,10195,10194,10193,10190,10496,10198,10202,10201,10200,10227,10226,10651,9945,10642,10601,9727,9728,9729)"
    }
  }
}