Part Number T21-1-4.00A-01-20 Circuit Breaker Accessories in stock with ready to ship. Get an instant quote for Sensata Technologies Inc part number T21-1-4.00A-01-20 by filling form below with your desired order quantity, targeted price and the expected order-fulfilment date. Get instant quote for T21-1-4.00A-01-20. Our dedicated account manager will get back to you within 15 minutes.