Hello
SCXI-1300 is just general purpose terminal block. It cannot be visible in MAX. Read the overview:
You can use the SCXI-1300 to connect input signals to the SCXI-1100, SCXI-1102 Series, and SCXI-1104 modules. The SCXI-1300 is a general-purpose terminal block with an onboard temperature sensor for cold-junction compensation. You can also use the SCXI-1300 with the SCXI-1181 and SCXI-1181K modules.
http://sine.ni.com/nips/cds/view/p/lang/pl/nid/1692
SCXI-1374 is just a handle:
The NI SCXI-1374 is a chassis handle for increased mobility. The SCXI-1374 kit includes one handle, which you can attach to either side of the SCXI chassis. You can also use two SCXI-1374 kits together to provide handles on both sides of your SCXI chassis.
http://sine.ni.com/nips/cds/view/p/lang/pl/nid/1641
mtwar