Single-Acting Spool - 612000001 612000001 $53.10 In stock Quantity: 1 Add to Bag Product Details 612000001 Spool only. May be installed in any MB-8 valve (except float spool). Plug the A port, use the B port. (A single-acting spool uses only one work port, powers a single-acting cylinder or motor.) Save this product for later Favorite